Solution:
The increase is the original: 3/5+ 10%.
So it was supposed to be done: 280/(3/5+ 10%)=400 yuan.
(2) The books produced by a school-run factory this month increased by 30,000 yuan. If VAT is paid at 17% of the value-added amount, how much VAT should be paid this month? (Please write down the calculation process)
Payable: 30,000 *17% = 5100 yuan.
(3) Dad's salary this month is 2 100 yuan. According to the regulations, the income tax shall be paid on the salary1.above 600 yuan. If you pay the personal income adjustment tax at the rate of 5%, how much should Dad pay this month? How much does he actually earn? (Please write down the calculation process)
Maturity: (2 100- 1600)*5%=25 yuan.
Actual income: 2 100-25=2075 yuan.
1. Application of area calculation of parallelogram, triangle and trapezoid.
1, PLA soldiers reclaimed a parallelogram vegetable field. Its bottom is 24 meters and its height is 16 meters. What is the area of this land?
s=ah 24* 16=384
2. Trapezoidal wheat experimental field with an upper bottom of 86m, a lower bottom134m and a height of 60m. How many square meters is its area?
s =(a+b)* h/2(86+ 134)* 60/2 = 6600
3. Triangular land with a bottom height of 358m and a height of 160m. What is the area of this land?
s=ah/2 358* 160/2=28640
Second, summarize the application questions
1. The People's Liberation Army Transportation Company transports a batch of coal. If each truck is loaded with 4.5 tons, it will take 16 cars to transport it at one time. If each truck is loaded with 6 tons, how many cars will it take to transport it all at once?
4.5* 16/6= 12
2. Students put flowers, each with 9 pots, which requires 36 people; If 18 people want to put it, how many pots should each person put?
36*9/ 18= 18
Third, the application of three-step calculation method
Taiyanggou Primary School held a math knowledge contest. There are 60 participants in the third grade and 45 participants in the fourth grade. The number of participants in the fifth grade is twice that in the fourth grade. How many people took part in the competition in the third grade?
45*2+45+60= 195
Fourth, meet the application problems
1, Zhang Ming and Li Hong set out from two places at the same time, facing each other. Zhang Ming walks 50 meters per minute and Li Hong walks 40 meters per minute. 12 minutes later, they met. How many meters are they apart?
(50+40)* 12= 1080
2. The distance between Party A and Party B is 255km, and two cars leave both places at the same time. Car A travels 48 kilometers per hour and car B travels 37 kilometers per hour. Two cars meet in a few hours.
255/(48+37)=3
5. List simple equations to solve practical problems
Xiangqun Stationery Factory can produce 250 pencil boxes per hour. How many hours can you produce 10000?
Suppose: X hours can produce 10000 pieces.
250x= 10000
x=40
Answer: 40 hours 10000.
Six, about the application of cuboids and cubes, the calculation of surface area and volume.
1, a rectangular iron box, length 18cm, width 15cm and height 12cm. What is the volume of this iron box?
18* 15* 12=3240
2. The side length of the cube is15cm. What is its volume?
15* 15* 15=3375
1, fill in.
(1) There are () simplest true fractions whose denominator is 12, and their sum is ().
(2) One conductor is 45 meters long, which is 14 meters shorter than the other, and the two conductors are * * * () meters.
(3) One conductor is 45 meters long, the other conductor is shorter than it by 17 meters, and the other conductor is () meters long.
(4) Addition and subtraction of fractions with different denominators, first (), then (), and then addition and subtraction.
(5) A batch of fertilizer was shipped 13 on the first day and 25 on the second day, and the remaining batch of fertilizer () was not shipped.
(6) Make the following fractions and decimals reciprocal.
0.75=( ) 25 =( ) 3.42=( )
58 =( ) 2. 12=( ) 4 14 =( )
2. Calculation problems
5 12 +34 + 1 12 7 10 -38 - 18 4 15 +56
12 -(34 -38 ) 56 -( 13 +3 10 ) 23 +56
3. Solve the equation
17+x = 23 45-x = 14 x- 16 = 38
Step 5 solve the problem
(1) There is a piece of cloth. It takes 78 meters to make a coat and 34 meters to make a pair of trousers, leaving 1 12 meters. How many meters is this cloth?
(2) An engineering team built roads, the first week was 49 kilometers, the second week was 29 kilometers, and the third week was less than the sum of the previous two weeks 16 kilometers. How much was repaired in the third week?
(3) In class, students spend 15 hours doing experiments, teachers spend 3 10 hours explaining, and students finish their homework independently in the rest of the time. It is known that each class is 23 hours. How long does it take for students to do their homework?
fill (up) a vacancy
1.0 m is to divide 1 m into () parts and take () parts.
2. The decimal unit of is (), and it has () such decimal units.
3. Yes, there is one in the room.
4. Fill in the appropriate scores in the brackets.
24 kg = () tons 4 meters 20 cm = () meters.
360m = () km 1 hour = () days.
5.= = = =( )÷9=44÷( )
6. The maximum true score is (), the minimum false score is () and the minimum simplest fraction is ().
7. Divide the 2m-long wood into 7 sections on average, each section is 1 m long, and each section accounts for the whole length.
8.+ means () plus (), and the total is ().
9.,,,, these scores can be turned into a finite score is ().
10. Rank the scores of the following groups in descending order.
,No. () > ()> ()
、4.5()>； ()& gt( )
Second, multiple-choice questions:
1. Among the following figures, not less than ().
a、 1 B、C、
2. Put 5 kg of salt into 20 kg of water, and the weight of salt accounts for () of salt water.
A, B, C,
3. There are () simplest real scores less than.
A, 3 B, 4 C, countless
4. And these two scores ().
A means the same; B, the size is equal; C, the decimal units are the same.
5. If A equals B, then A () B.
A, greater than B, equals C, less than.
Third, judge the question.
1.3 kg of water is as heavy as 1 kg of water. ( )
2. Tons of cotton = tons of iron. ( )
3. 1 is the simplest score. ( )
4. Because the ratio is very small, the decimal unit of is smaller than that of. ( )
5. The true score is always less than the false score. ( )
6. Rice is bigger than rice. ( )
7. The numerator and denominator of the simplest fraction have no common factor. ( )
Fourth, oral calculation.
+0.5 + 3.6+ +
2.4- 1 +3.6 6.43- -0.375
5. Calculate the following questions. (as simple as possible)
1+ - + - - -
2. 15-( - ) 2.85+ +2. 15+ 3.4-(0.25+ )
Sixth, solve the equation.
+x = 5.6 x-= x-( 1.4+)= 1.8
Seven, column calculation.
1.A number is 0.75 more than b number. What is the sum of the two numbers?
2. Subtract the difference of 3.25 from a number, and the result is 2.5. What's this number?
Eight, application questions.
There are 48 students in 53 classes, including 2 boys1. What percentage of girls are in the class? What is the ratio of boys to girls?
2. To produce the same parts, from 27 pieces in 12 hours to 13 pieces in 6 hours and 19 pieces in 8 hours. Who can do it fastest? Who is the slowest?
3. Build a road with a length of 1500m. If the whole project is completed in the first week and the whole project is completed in the second week, what is the score for completing the whole project?
Wang Lin read a book. On the first day, he finished reading the whole book. The next day and the third day, he read a whole book more than the first day. After three days, how many parts are left in the whole book?
5. There is a rectangle with a circumference of 68 cm, which is known to be 2 cm long and how many centimeters wide.
Responder: Folding Angel ylq- Scholar Level 3 1- 18 10:07.
What are you doing?
Respondent: Xiao's probation period is Grade 1 1-20 13: 12.
Formulas for solving the application problems of fractions and percentages
The unit "1" is known: unit "1"× corresponding fraction = corresponding quantity.
Unit 1 or unit 1 is unknown: corresponding quantity ÷ corresponding score = unit 1.
Formula for finding the fraction (or percentage) of one number and another:
One number ÷ another number = A number is a fraction (or percentage) of another number?
Find out how much one number is more than another:
Excess ÷ unit "1" = how many fractions (or percentages) one number is more than another.
Find out how much one number is less than another:
Small quantity ÷ unit "1"= how many fractions (or percentages) one number is less than another.
(Note: The words "more" and "less" here can also be replaced by words such as "increasing production" and "saving". )
(Note: Example: (1) There are 120 peach trees in the orchard, and the number of pear trees is 20% more than that of peach trees. How many pear trees are there in the orchard?
(2) There are 120 peach trees in the orchard, which is 20% less than that of pear trees. How many pear trees are there in the orchard?
Analysis idea: first find out the unit "1" and determine whether it is known or unknown. If the unit "1" is known, use multiplication; if the unit "1" is unknown, use division. "A few points more (less) than who" is "a few points of 1+(-)". )
Formula: (1)120× (1+20%)
(2) 120÷( 1-20%)
Formulas to solve the application problems of discount, profit, interest and tax.
Meaning: "20% off" means: the current price is 20% off the original price; "15% discount" means that the current price is 85% of the original price.
Formula:
Current price = original price × discount (usually written in percentage form)
Profit = selling price-cost
Interest = principal × interest rate× time
After-tax interest = principal × interest rate× time× 80% (note: national debt and education savings are not taxed)
Tax payable = tax payable × tax rate
Formulas and key sentences about the circumference and area of a circle
The ratio of the circumference to the diameter of a circle is called pi. π = C ÷ d
Find the perimeter of a known diameter: C = πd Find the diameter of a known perimeter: d = C ÷π.
Find the perimeter of a known radius: C = 2πr Find the radius of a known perimeter: r = C÷π÷2.
Find the area of known radius: S =πr
Find the area of known diameter: r = d÷2.
S = πr
Find the area of the known perimeter: r = C÷π÷2.
S = πr
Semicircle circumference = C ÷ 2+d (note: semicircle circumference = 5. 14r, suitable for filling in the blanks)
Semicircular area = S ÷ 2
Divide a circle into several parts evenly and make an approximate rectangle. (See book for pictures)
(1) Area of rectangle = area of circle.
(2) The length of the spliced rectangle = half the circumference (length =)
(3) The width of the spliced rectangle = the radius of the circle (width = r)
Fill in the blanks. (1 minute per grid, ***20 points)
(1) A number consists of three 100, two 10 and five 0.0 1. This number is written as ().
2. 7 tons and 560 kilograms = () tons, 1 hour = () minutes.
(3) decompose BaZi 80 into prime factors, (180 =)
(4), the scoring unit is (), plus a scoring table like ().
Bit gets the smallest prime number.
[5], the ratio of 2.7∶ 1 to the simplest integer is (), and the ratio is ().
[6], a triangle has at least () acute angles.
At one time, a steel cylinder could be cast into a cone with equal bottom and equal height.
(8) Remove the rice with a 5-meter cloth. How many meters are left? The formula is ().
Levies, circle is axisymmetric circle, its axis of symmetry is ().
⑽. The number of winners in the primary school mathematics competition is ***30, and the ratio of the number of first, second and third prizes is.
1∶2∶3, and the number of people who won the third prize is ().
⑾ The circumference of a circle is 18.84 cm, and the area of this circle is ().
On the map with the scale of 1: 3000000, the distance from Beijing to Guangzhou is 6.
Cm, the actual distance from Beijing to Guangzhou is about () kilometers.
Second, the judgment question. (Mark "√" correctly in brackets and "×" incorrectly) (* * 8 points)
The greatest common divisor of (1) 16 and 24 is their least common multiple. ( )
(2) The circulating decimal number is 0.5, and the rounding to two decimal places is about 0.55. () 1. The quality of a barrel of milk is 8/5kg= 1.6kg, which is distributed to four children on average, and each child gets 1.6/4=0.4kg.
2.5/ 12÷3/4=5/ 12×4/3; 3/50÷6/5=3/50×5/6; 2/3÷3/4=2/3×4/3
3. 15*5/3=25; 3/5+05m of 65438 =15 * 3/5 = 9.
4. A car traveled 30km in 0.75 hour, and the speed per hour was 30/0.75=40km.
5.8/9÷3 = 8/27 & lt； 24/27=8/9; 10/ 1 1÷ 10/ 1 1 = 1 & gt； 10/ 1 1; 5/6÷ 1/4 = 10/3 = 20/6 & gt； 5/6; 9/8/9 = 8 1/8 = 10 and1/8 > 9; 3/4× 1/6 = 1/8 & lt； 3/4÷ 1/6=9/2
6. 10/2 1÷5/ 14=4/3; 2/7÷9/ 14=4/9; 7÷ 14/ 15= 15/2; 18/25÷9/ 10=4/5; 5/ 12÷5/6= 1/2; 15÷20/2 1=63/4
7.24÷ 1/3-56=24*3-56=72-56= 16; (6/35+4/2 1)÷4/7=6/35*7/4+4/2 1*7/4=3/ 10+ 1/3= 19/30;
2/5÷3/4×5/2=2/5*5/2÷3/4= 1÷3/4=4/3; 49/5×7/8÷7=49/5*(7/8÷7)=49/5*( 1/8)=49/40;
1/2×( 1/3+5/6)÷5/7= 1/2×7/6÷5/7= 1/2*49/30=49/60;
2/3÷3/4×(5/8- 1/2)=2/3÷(3/4× 1/8)=2/3*4/3*8=64/9