Solve six primary school math problems. To process .

1. The speed ratio of the two cars is 5:8, and the two cars drive out of A and B at the same time, and the two cars meet at a distance of 24 kilometers from the midpoint, how many kilometers are the two kilometers apart?

24*2 (8 13-5 13) = 208 km.

A: The two places are 208 kilometers apart.

2. A rectangular vegetable patch, 100 meters long and 60 meters wide, drawn on a map with a scale of 1:1000, how big is the distance on the map?

100*1 1000=m,60*1 1000=m.

A: The picture is rectangular in length and width.

3. A and B two trains of cars drive out of the two places at the same time, and the ratio of the two cars to the remaining distance is 5:3 after 3 hours, and it is known that car A travels 48 kilometers per hour and car B travels 57 kilometers per hour. How many kilometers are the two places apart?

48 + 57) * 3 (5 8) = 504 km.

A: The two places are 504 kilometers apart.

4. Use a wire 88 cm long to enclose a rectangle, the ratio of the length and width of the rectangle is 7:4, find out how many square centimeters the area of this rectangle.

88 [2*(7+4)] = 4 cm. 4*7*4*4=448 square centimeters.

A: The area of this rectangle is 448 square centimeters.

5. A bamboo pole is 4 meters long, standing upright on the ground, and its shadow length is measured to be meters, and the shadow of a good building is meters long. How tall is this building?

Rice. A: The height of this building is 28 meters.

6. The ratio of ballpoint pen and pencil is 4:3, buy 20 ballpoint pens and 21 pencils to share the yuan, what is the unit price of the ballpoint pen?

Yuan. A: The unit price of a ballpoint pen is 2 yuan.

The first question is whether it is 208 kilometers? The main thing is equation processing.

The second question is 10 cm long and 6 cm wide.

I'm too lazy to write here, look for me, and I'll help you solve it!!

1.Answer:

The speed ratio of cars A and B is: 40:30=4:3

When A finishes the race, B still has 1 4 left to finish.

The distance between a and b = 30 (1 4) = 120 km2Vial weight: (kg.)

Carboy weight: kilograms.

1. According to the ratio of kilograms of pears in the two fruit stores of A and B is 5:4, if the original 5x kilograms of store A are set up, then store B is 4x

5x-45 ):4x+45)=5:7

Solution x=36

Therefore, the original store is 36*5=180 kg.

2. Set x questions to answer correctly, answer incorrectly or not answer (20-x).

10x-5 (20-x) = 95 x = 13 If you answer 13 questions correctly, your score will be no less than 95 points.

3. Let the numerator be x and the denominator be (100-x).

x+21) (100-x+29)=2 3 x=39, the original fraction was 39 61

Adopt it

1.The total remains the same, A used to account for 5 9, now it accounts for 5 12, a decrease of 5 36, which is the 45 kilograms of pears, so the total is 45 divided by 5 36, giving 324 kilograms, and A is 5 9 of them, giving 180 kilograms.

2.Generally, it is 50 points when it is right, less than 95 points, the number of questions must be greater than 10 questions, and each pair of questions not only does not need to deduct 5 points compared to 50 points, but also adds 10 points, a total difference of 15 points, that is to say, more than 15 points for one question, 90-50 = 45, 45 divided by 15 = 3, so there are 3 questions, that is, a total of 10 + 3 = 13 questions are answered correctly.

3.If the numerator is added to 21 and the denominator is added to 29 to get a new fraction, then the sum of the numerator and the denominator is 100 + 21 + 29 = 150, and 2 3 is obtained after dividing the numerator and denominator by a number at the same time, then the numerator before the month is 2x, the denominator is 3x, the column formula 2x + 3x = 150, the solution is x=30, then 2x=60, 3x=90, subtract 21, 29 respectively, and get the original numerator is 39, The denominator is 61

1.Solution: The original x kg of fruit in the first store has been 4 5x kg (x-45) :( 4 5x+45) = 5:7

7(x-45)=5(4/5x+45)

7x-315=4x+225

3x=540

x=1802.Solution: At least answer at least X question correctly with no less than 95 points, then the wrong question should be (20-x) question 10x-5 (20-x) = 95

15x=195

x=133.The sum of the numerator and denominator of the new fraction is 150, which is equal to 2 3 after the fraction, so this fraction is 60 90, so the original fraction is 39 61

1. If A has x kilograms, then B has 4 5x kilograms.

It can be obtained that (4 5x+45) = 7 5 * (x-45) gives x = 180

2. If the correct answer is x question, then the wrong answer or no answer is (20-x) question.

The total score equation 10x-5*(20-x)>95 gives x=13

3. If the numerator is x, the denominator is 100-x.

Listing equations (x+21) (100-x+29)=2 3 gives x=39