Solution: 33300

9999? 1? 99? 2?

Original formula = 3 = 333300

Party A, Party B and Party C all have deposits in the bank. The deposit amount of Party B is 100 yuan less than that of Party A, and the deposit amount of Party C is twice less than that of Party A and Party B..

2

People's deposits are within 300 yuan, and A's deposits are 5 of C's, so how many deposits do A, B and C have?

Solution: A 800, B 1500, C 2000.

Let A be X yuan, B be (2x- 100) yuan and C be (3x-400) yuan. 2

Column equation: 5(3x-400)=x Solution: x=800.

3. China School distributes washing powder to the teachers in the thinking training class. If you give each male teacher 3 packages and each female teacher 4 packages, there will be 8 more packages. If you give each male teacher four bags and each female teacher five bags, you will lose seven bags. It is known that there are more male teachers than female teachers 1, so how many packets of washing powder does * * * have?

Solution: 60

Prompt: From "3 packages for male teachers and 4 packages for female teachers" to "4 packages for male teachers and 5 packages for female teachers", each teacher increases 1 package, and * * uses 8+7 = 15 package, which means there are 15 teachers, including 8 male teachers and 7 female teachers.

3× 8+4× 7+8 = 60 packs.

The store bought a batch of pens and decided to sell them at the price of each 9.5 yuan. It sold 60% in the first week, but 84 yuan still failed to recover the full cost. After another week, all the pens were sold out, with a total profit of 372 yuan. So how much did the store spend on these pens?

Solution: 6.4 yuan

First, find out the total number: (372+84) ÷ 9.5 = 48 48 ÷ (1-60%) =120. 372÷ 120=3. 1 9.5-3. 1 = 6.4 yuan

We stipulate that two people take turns to do a project, that is, the first person does an hour, the second person does an hour, then the first person does an hour, then the second person does an hour, and so on until it is completed. If it takes 9.8 hours for Party A and Party B to do a project in turn and 9.6 hours for Party B and Party A to do the same project in turn, how many hours will it take for Party B to do this project alone?

Answer: the time it takes each person to do it twice: a and B.

5 hours 4.8 hours

4.6 hours and 5 hours

∴ A's 0.4-hour project is equal to B's 0.2-hour project, B's efficiency is twice that of A, and A's 5-hour task can be completed in 2.5 hours.

B It takes 2.5+4.8 = 7.3 (hours) to complete this project alone.

6. The distance between Party A and Party B is120km. Buses and trucks leave from Party A and go to Party B at the same time. After the bus arrived at Party B, it immediately returned along the original road, and Party C met the truck on the way. After that, the bus and truck continued to move forward and turned back immediately after arriving at A and B respectively. As a result, the two cars happened to meet at C. It is known that the two cars met for the first time two hours after departure. So how many kilometers is the speed of the bus?

Solution: (sketch)

At the first meeting, the two cars walked two full distances together, and at the second meeting, the two cars walked two full distances more than at the first meeting. When the bus and truck meet for the first time, their respective distances are equal to the distance when they meet for the second time. The two encounters are at point C. Let the distance between B and C be 1, the distance between A and C be 2, and the distance between B and C be120 ÷ 3 = 40.

The bus speed is (120+40) ÷ 2 = 80 (km/h).

7. As shown in Figure 5, on a 490-meter-long circular runway, the runway between point A and point B is 50 meters long, both of which start from point A and point B at the same time and run in opposite directions. After they met, B immediately turned around and ran in the same direction as A. At the same time, A speeded up 25% and B speeded up 20%. As a result, when A runs to point A, B just runs to point B. If A later.

?

Solution: After the encounter, B's speed increased by 20%, and he ran back to point B, that is, the round-trip distance was the same. B's speed before and after the change is 5: 6, and the time spent is 6: 5.

Suppose A ran 6 units when they met, then it took 5 units to run back to Point A after they met. Let's assume that the original speed per unit time, V A, is derived from the following question:

6V A+5× V A× (1+25%) = 490, so V A = 40.

100

The distance from point A to the intersection is 40× 6 = 240, ∴ V B = (490-50-240) ∴ 6 = 3.

100

After their speed changes, the speed of A is 40× (1+25%) = 50, and the speed of B is 3 (1+20%) = 40. From the intersection, when A catches up with B, A takes one more lap than B,

∴ A * * * ran 490 ÷ (50-40) × 50+240 = 2690 (meters).

8, a nifty pig 25 yuan, Garfield is cheaper than nifty pig, but the price is also an integer yuan, and it costs 280 yuan to buy two nifty pigs. How many lovely pigs did you buy?

Solution: Suppose you buy X cute pigs, then the cat buys x-2.

Suppose a cat is one yuan, then 25x+a(x-2)=280.

X=(280+2a)/(25+a)=2+230/(25+a)

So 25+a is the divisor of 230, 25+a=46 a=2 1, then X=7, so I bought seven.

9. There are some natural numbers, and the sum of the remainder divided by 7 and the quotient divided by 8 is equal to 26, so what is the sum of all these natural numbers? Solution: If you divide by 7 and leave 0, then the quotient of dividing by 8 is 26, and the number is 26*8+2=2 10.

If you divide by 7 and 1, the quotient of dividing by 8 is 25, and the number is 25*8+4=204.

If you divide by 7 and leave 2, then the quotient divided by 8 is 24, and the number is 24*8+6= 198.

If you divide by 7 to get 3, the quotient of dividing by 8 is 23, and the number is 23*8+ 1= 185.

If you divide by 7 to make it greater than 4, then the quotient of dividing by 8 is 22, and the number is 22*8+3= 179.

If you divide by 7 to make it greater than 5, then the quotient of dividing by 8 is 2 1 and the number is 2 1*8+5= 173.

If you divide by 7 and leave 6, then the quotient of dividing by 8 is 20, and this number is 20*8= 160 or 20*8+7= 167.

So the sum of all these natural numbers is 1476.

10 and three classes have 44,465,438+0 and 34 students respectively. They rented a car for a spring outing. It is stipulated that there are three classes, one by cart, one by medium-sized car and one by car. It is understood that large, medium and small cars can accommodate 7, 6 and 5 students respectively, and each car has 80, 70 and 60 yuan.

Solution: 44 students take the car, 4 1 student take the bus and 34 students take the bus, so the lowest fare for wasting seats is 80 * 5+70 * 7+60 * 9 = 1430 yuan.

Considering the single fare of three kinds of cars, the big car 1 1 3/7 yuan/person, the medium car 1 1 2/3 yuan/person and the small car 1 2 yuan/person, it can be seen that the big car is the most expensive.

Considering that there are many people in the cart, try not to waste seats. 4 1 person cart, 34 people get on the bus and 44 people get on the bus.

The ticket price is 80*6+70*7+60*9= 1440 yuan, which is relatively expensive.

It can be seen that the decisive role is not to waste seats, so it will cost at least 1430 yuan.

1 1. At present, there are several cylinders with bottom radius and bottom height of 1 and several cylinders with bottom radius and bottom height of 2, and their volume sum is 50? The sum of the surface areas is 120? How many cylinders are there in a * * *?

Solution: 15

12 As shown in the figure, draw two small and medium squares in a square, so that the three squares have common vertices, thus dividing the big square into square area A and L-shaped areas B and C. It is known that the ratio of perimeters of the three areas A, B and C is 4:5:7, and the area of area C is 48. Find the area of a big square.

Solution: 98

The ratio of perimeter is equal to the ratio of side length. Let the side lengths of A, B and C be 4a, 5a and 7a respectively.

A2-25 A2 = 48 Find A2 = 2；; The area of the big square = 49a2=98.

13, the cubic of a natural number has exactly 100 divisors, so the natural number itself has at least one divisor. Solution: Let this natural number be a1b1* a2b2 * ... * anbn.

Then its cubic power is a1(3b1) * a2 (3b2) * ... 30 billion pounds.

Its divisor is (3b1+1) (3b2+1) ... (3bn+1) =100.

We now hope that (b1+1) (B2+1) ... (bn+1) will take the minimum value.

1 100=4*25

At this time, b 1= 1 b2=8.

(b 1+ 1)(B2+ 1)= 18

2) 100= 10* 10

At this time, b 1=b2=3.

(b 1+ 1)(B2+ 1)= 16

So this natural number itself has at least 16 divisors.