The first volume of the sixth grade added the answers to typical mathematical application problems.
First, the basic knowledge of the circle: the diameter is expressed in letters = the radius is expressed in letters = R.
The circumference of a circle is expressed in letters =C=πd or
C = 2π r. The area of a circle is expressed in letters: s=πr? . π=3. 14
1. Draw a circle with a circumference of 12.56 cm, and mark the center and one with letters.
The radius of the bar, and then find the area of the circle.
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Area: 12.56/3. 14/2=2 (cm)
2*2*3. 14= 12.56 (square centimeter)
A: The area is 12.56 cm.
There is a circular lawn in the school. Its diameter is 30 meters. The surface of this lawn
How many square meters is the product? If you put a pot of chrysanthemums every 1.57 meters around the lawn, how many pots of chrysanthemums should you prepare? 30/2= 15 (cm)15 *15 * 3.14 = 706.5 (m)
706.5/ 1.57=40 (pots) A: The area is 706.5 meters, and 40 pots of chrysanthemums should be prepared.
3. the diameter of the round flower bed is 10 cm, and a 2 is laid around it.
A m-wide path. How many square meters is this path?
10/2=5 (cm) 5+2=7 (cm) square difference solution: S=π(R? -r？ ) =3. 14*(7? - 5? )
=3. 14*24 =75.36 (cm) A: The area of this path is 75.36 cm. The hour hand of the big clock is 0.3 meters long. How long did the tip of this hour hand travel in 1 day?
Rice? How many square meters is the sweeping area? 0.3*2*3. 14= 1.884 (m2)
A: I left in one day 1.884.
rice. The sweeping area is 0.2826 square meters. 5. The range of automatic rotary sprinkler irrigation device on the park lawn is 10 meter. How wide can it spray irrigation? 10 *10 * 3.14 = 314 (square meter)
A: He can spray irrigation on an area of 3 14 square meters. 6. There is a ring. The circumference of the inner circle is 3 1.4 cm, the circumference of the outer circle is 62.8 cm, and what is the width of the ring?
3 1.4/3. 14/2=5 (cm) 62.8/3. 14/2= 10 (cm) 10-5=5 (cm)
7. Xiaodong has a bike. The diameter of the wheel is about 66 cm. If the average speed is 100 laps per minute, then the distance from home to school is 4 144.8 meters, which is about.
How many minutes will it take?
66*3. 14=207.24 (cm) 207.24* 100=20724 (cm) =207.24 (m)
4 144.8/207.24=20 (minutes)
A: It will take 20 minutes. 8. Round bottom boiler with circumference of1.57m.. bottom
How many square meters is the product? (The number shall have two decimal places)1.57/3.14/2 = 0.25 (m) 0.25 * 0.25 * 3.14 = 0.19625 (m? ) 0.20 (square meter)
A: The building area is 0.2 square meters. Second, the percentage 1, the original price of a commodity is 20% less than the current price, the current price is 1028 yuan, and the original price is
how much is it?
1028 * (1-20%) = 822.4 (yuan) a: the original price was 822.4 yuan. 2. A factory invested 320,000 yuan to build a new production workshop, less than planned.
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Ten thousand dollars, how much less investment than planned? 8/32* 100%=25% A: 25% less than planned. 3. Xixiang has a bumper harvest of litchi this year, with a yield of 3.6.
Ten thousand tons, an increase over last year.
It produced 20%. What was the yield of litchi in Xixiang last year? 3.6/( 1+20%)=3 (tons) a: the output is 3 tons. 4. build a highway,
Team A repaired 60% of the total length, while Team B repaired the total length.
30%, Team A has built 27 kilometers more than Team B. How many kilometers is this highway? 27/(60%-30%)=90 (ton)
Answer; This road weighs 90 tons. 5, son
Children's playground tickets were originally 20% off for each 30 yuan during the Spring Festival.
Discount, how much is it for Mr. Liu's family of three to buy tickets at the amusement park?
30*3*80%=72 (yuan) 30*3-72= 18 (yuan)
A: A * * * can save 18 yuan. 6. A TV set is now priced at 6000 yuan, which is profitable.
20%, this TV set
What's the buying price? 6000*( 1-20%)=4800 (yuan) A: The purchase price of this TV is 4800 yuan. 7. Miss Li put 2000
Rmb is deposited in the bank for five years at an annual interest rate of.
That's 4. 14%. How much money can Miss Li get back when it expires? (Interest tax is 5%. )
2000+2000 * 5 * 4.14% * (1-5%) = 2393.3 (yuan) 8. The flour yield of a wheat is 85%, which requires grinding 13.6 tons of flour.
Need this.
How many tons of wheat? 13.6/85%= 16 (tons) A: It needs 16 tons of wheat. 9. The clothing store bought two clothes at the same time, each of which got 120.
Yuan, but
One of them made 20% and the other lost 20%. Did the two clothes sold by the clothing store make money or lose money? 120 ÷ (1+20%) =100 (yuan)
100+ 150=250 (yuan) 250-240= 10 (yuan) answer: compensation 10 yuan.
120 ÷ (1-20%) =150 (yuan)
120×2=240 (yuan)
Third, compare and proportion 1, and make a 600.
The ratio of flour, red beans and sugar is 3:2: 1. How many grams of flour, red beans and sugar do you need? 3+2+ 1 = 6 600 * 1 = 100(g)600 * 2
=200 (grams)
6 6
600* 3 =300 (grams) 6 A: 300 grams of flour, 200 grams of red beans, sugar 100 grams. 2. The circumference of a rectangle is
24 cm, the length-width ratio is 2: 1, how many square centimeters is this rectangle? 24/2= 12 (cm) 2+ 1=3 (cm) 12* 1
=4 cm
three
12* 2 = (cm) 8 3
4*8=32 cm
A: The area is 32 cm. 3、
The total length of a cuboid is 96 cm, the height is 4 cm, and the length-width ratio is 3 ∶2. What is the volume of this cuboid?
96/4=24 cm
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3+2 = 5cm 24-4 = 20cm
five
20* 3 = 12 (cm) 20* 2
=8 (cm) 8* 12*4=384 (cm？ )
The volume of this rectangle is 384 cm? . 4, A, B two construction teams * * * road 360 meters, the length of the two teams is
At 5: 4, how many meters did Team A repair more than Team B? 5+4=9 360* 5 =200 (m) 360* 4 = 160 (m)
nine
nine
200- 160=40 (meters) A: It was repaired by 40 meters. 5. There are 42 computer interest groups in a school. The ratio of male to female is 4: 3. How many boys are there?
6. There are two baskets of fruit. The first basket weighs 32kg. After taking out 20% from the second basket, the weight ratio of the two baskets of fruits is 4:3. How many kilograms were there in the original two baskets of fruit? Solution: Let the fruit in the original box B be X.
Kilogram. After taking out 20%, the fruit in the second basket is (1-20%)X kg, that is, 0.8X kg. 32:0.8X=4:3 Solution: X = 30kg.
30+32 = 62kg
A: * * * There are 62 kilograms.
7. The ratio of the three internal angles of a triangle is 2:3:4. What are the degrees of these three internal angles? 2+3+4=9
180 * 4 = 80 9 A: 40, 60 and 80 respectively. 180* 2 =40
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180* 3
=60
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8. A naughty family of three and a smiling family of four go to a restaurant for dinner, with a total meal fee of *** 280 yuan. The two families decided to share the cost of meals according to the number of people. How much does each family pay? 3+4=7 280*
3 = 120 (yuan) 280* 4 = 160 (yuan)
A: The naughty family made friends 120 yuan, and the smiling family made friends 160 yuan. 10, in the "Learn from Lei Feng" activity, students in grade five and grade six did 80 good deeds on average, among which the ratio of the number of good deeds in grade five and grade six was.
3︰5。 How many good deeds did the sixth graders do? 80*2= 160 (a) 3+5=8 160* 3 =60 (a)
eight
160* 5
= 100 (piece)
eight
A: The fifth grade made 60 yuan and the sixth grade made 100 yuan.
Sorry, it may be a little messy. This is all I found. . Please forgive me if there is any mistake. After all, resources and time are limited, and there may not be enough questions. But I've already helped you, dear. Please correct me if there are any mistakes, and I will definitely correct them! ! !