The Olympiad Problem of Graphic Perimeter in the First Volume of the Sixth Grade of Pingshan Primary School in Jiangmen City

1. There was an exam, and the sixth grade Chinese passed 95% and the math passed 90%. There are 34 people who have passed both subjects, but no one has failed both subjects. How many people are there in the sixth grade?

34÷95%=36

34÷90%=38

So 38-36=2 people have passed both doors.

There are 36+38-2=72 students in Grade Six.

2. Party A is equal. Party A recruits 24 and Party B withdraws 14. Now Party A has more than Party B 19/6. So what was it?

Assuming that the original number of two groups is x, the following equation can be obtained.

[(x+24)-(x- 14)]/(x- 14)= 19/6

38/(x- 14)= 19/6

x- 14= 12

x=26

A: The original Party A and Party B each had 26 people.

3. A commodity is sold at a profit of 13 yuan per piece in 7 yuan, and at a profit of 12 yuan per piece in 23 yuan. What is the purchase price of this commodity?

(7-X)* 13 =(23/2-X)* 12

X=47

4.AB also has passenger buses. The two cars met for the first time at 50 kilometers in City A, and returned immediately after arriving at the station. When they returned, they met again at 40 kilometers in City B.. How many kilometers are the two cities apart?

50*3-40= 1 10 (km)

5. The length of the road around the lake is1.920m.. Party A and Party B are racing on the highway along the lake, and they both start from the same place and go in opposite directions at the same time. Party A walked faster than Party B, and they met in 12 minutes. If both of them walk 16 meters per minute, then the meeting place is 20 meters away from the previous one.

(1) Find their original walking speed.

1920/12 =160 (m/min)

1960/( 160+ 16 * 2)*(X+ 16)-X * 12 = 20

X=70

A: 90 meters per minute.

B: 70 meters per minute.

6. Party A and Party B run on the 400-meter circular track. If they run in the same direction, they meet every 3 minutes and 20 seconds. If you run in the opposite direction, you will encounter it every 40 seconds. Q: What is the speed of the fastest runner? 60*3+20=200 (seconds)

(400/200+400/40)/2=6 (meters per second)

7. 1 1 Students are using the 10 laundry basket to carry earth. Do you know how many students carry dirt and how many students carry dirt?

Suppose X people are picking up soil and (1 1-X) people are lifting soil.

Because when picking soil, one person picks two baskets and * * * picks 2X baskets.

Two people carried a basket, so * * * carried the 1/2( 1 1-X) basket.

1/2( 1 1-X)+2X = 10

X=3

1 1-3=8 people.

Three students carry the earth and eight students carry it.

8. The Amazon River is 6480 kilometers long, and the Yangtze River, the third largest river in the world, is one third shorter than the Amazon River. Is the Yangtze River longer?

6480 * (1-1/36) = 6300 km.

9. 1 The price of drugs dropped from 10 bottles in 24 yuan to 5 bottles in 9 yuan. How much did each bottle drop? What percentage?

24/ 10=2.4 9/5= 1.8

2.4- 1.8=0.6 (decrease)

0.6/2.4=0.25=25% (percentage)

10, the number of stamps in Xiaolan and Xiao Fang is equal. Later Xiaolan gave her 15 stamp to Xiao Fang. At this time, the number of stamps between them is 2: 5. How many stamps did Xiaolan and Xiao Fang originally have?

Solution: Let the original stamp number of Xiaolan and Xiao Fang be X,

(x- 15)/(x+ 15)=2/5

5(x- 15)=2(x+ 15)

5x-75=2x+30

3x= 105

X=35 (pieces)

A: Xiaolan, Xiao Fang originally had 35 stamps each.

1 1 and (3) students subscribe to three kinds of publications, of which 80% students subscribe.

60% at most, because the minimum subscription is teenagers, so that's all at most.

12. The aspect ratio of a rectangle is 1.5: 1. The circumference of this rectangle is 48 cm. How many centimeters is the length of this rectangle more than the width?

This is actually quite simple. The aspect ratio is 1.5: 1, which means that the length is 1.5 and the width is 1. Isn't the circumference exactly five? Divide 4.8cm by 5, you can get how many centimeters one is, which is 9.6, and then you can calculate the length as 10.

13. Liu Bing wants to buy some greeting cards for teachers and classmates during New Year's Day. As the price of greeting cards is reduced by 20%, he can buy six more cards with the same money. How many cards is Liu Bing going to buy?

Buy x sheets.

x/( 100%-20%)-x=6

x/80%-x=6

x5/4-x=6

x 1/4=6

x=24

I bought 24 tickets.

14. On a map, the distance from Shanghai to Beijing is 12 cm. A plane travels at 720 kilometers per hour, and it takes two hours to fly from Shanghai to Beijing. Find out the scale of this map.

12/720*2* 1000* 100= 1/ 12000000

The picture scale is 1: 1200000.

15, during the New Year's Day, Gome Mall held promotional activities. The original color TV set is 2800 yuan, and the current price is lower than the original price by 700 yuan. What's the current price? What percentage of the original price is the current price?

2800-700=2 100 yuan

The current price is 2 100 yuan.

2 100÷2800× 100%=75%

The current price is 75% of the original price?

16, a bus from A to B has traveled 120 km, and the ratio of remaining distance to driving distance is 2: 3. How many kilometers is this bus from B?

120 ÷ 3 = 40km

2× 40 = 80km