Tisch
1. The distance between the two stations is 275 kilometers. The local train goes from Station A to bilibili at a speed of 50km/h, and after 1h, the express train goes from bilibili to Station A at a speed of 75km. How many hours after the local train leaves, will you meet the express train?
Solution: Let the local train meet the express train one hour after the express train leaves.
50a+75(a- 1)=275
50a+75a-75=275
125a=350
A=2.8 hours
2. It is known that the profit of a store in March is 654.38+10,000 yuan, and the profit in May is1320,000 yuan, and the monthly growth rate in May is 10 percentage point higher than that in April.
Solution: Let April profit be X.
Then x * (1+10%) =13.2.
So x= 12.
Let the growth rate in March be y.
Then10 * (1+y) = X.
y=0.2
=20%
So the growth rate in March was 20%
3. A batch of books are distributed to Class 1 10 and Class 2 15. How many books have been distributed in both classes now?
Solution: Let's assume that there are a total of books.
Class number =a/ 10
Number of Class Two =a/ 15
Then they are evenly divided into two categories, each of which is a/(a/10+a/15) =10×15/(10+15) =/kloc.
4. A bundle of 96m cloth is made for a class of Grade 6, and 15 is 33m cloth. According to this calculation, which class is the most suitable for these fabrics to make school uniforms? (1 class 42, class 2 43, class 3 45)
Solution: let 96 meters be done for person A.
According to the meaning of the question:
96:a=33: 15
33a=96× 15
A about 43.6
So it is suitable for Class 2, with a surplus, but not much. It is not enough to do it for Class Three.
extreme
1. A car travels from place A to place B at a speed of 40 kilometers per hour. After 3 hours, due to the rain, the average speed was forced to drop 10km. The result arrived in B 45 minutes later than expected. Find the distance between a and B.
Solution: Let the original time be one hour.
45 minutes =3/4 hours
According to the meaning of the question:
40a = 40×3+(40- 10)×(a-3+3/4)
40a= 120+30a-67.5
10a=52.5
A=5.25=5, 1/4 hours =2 1/4 hours.
So the distance between Party A and Party B is 40×2 1/4=2 10 km.
2. The school arranges dormitories for boarding students. If there are seven people living in each dormitory, no six people can't arrange it. If there are 8 people living in each dormitory, then there are only 4 people living in one dormitory, and there are 5 empty dormitories. How many people are there?
Solution: There is room A, with 7a+6 people in total.
7a+6=8(a-5- 1)+4
7a+6=8a-44
a=50
Someone =7×50+6=356 people
3. One kilogram of peanuts can fry 0.56 kilograms of peanut oil, so how much peanut oil can be fried in 280 kilograms?
Solution: Suppose you can fry one kilogram of peanut oil.
1:0.56=280:a
A = 280× 0.56 = 156.8kg
Complete formula: 280 ÷1× 0.56 =156.8kg.
Tisso
1. The locksmith class in a workshop is divided into two teams to watch the tree planting work. There are twice as many people in the first team as in the second team. If 16 people are transferred from the first team to the second team, the remaining number of people in the first team is 3 people less than half of that in the second team. What is the original number of the first and second teams?
Solution: Team B originally had A, while Team A had 2a.
Then according to the meaning of the question:
2a- 16 = 1/2×(a+ 16)-3
4a-32=a+ 16-6
3a=42
a= 14
Then team B was originally 14, and team A was originally 14×2=28.
At present, team B 14+ 16=30 people, and team A = 28- 16= 12 people.
2. The tree planting team of June 1st Squadron went to plant trees. If everyone plants five trees, there are still 65,438+04 seedlings left. If each race has seven trees, there will be six fewer seedlings. How many people are there in this team? A * *, how many seedlings?
Solution: There is one person.
5a+ 14=7a-6
2a=20
a= 10
A * * * has 10 people.
There are 5× 10+ 14=64 saplings.
A barrel of oil weighs 50 kilograms. Half of the soybean oil poured out for the first time was less than 4 kilograms, and the remaining three-quarters were two and two-thirds kilograms more for the second time. At this time, the barrel filled with oil weighs one third of a kilogram. How much oil was there in the original barrel?
Solution: Let the oil weigh one kilogram.
Then the barrel weighs 50-a kilograms.
Pour out 1/2a-4kg for the first time, leaving 1/2a+4kg.
Pour out 3/4× (1/2a+4)+8/3 = 3/8a+17/3kg for the second time, leaving1/2a+4-3/8a-17/3 =/kloc.
According to the meaning of the question:
1/8a-5/3+50-a= 1/3
48=7/8a
A = 384/7kg
There used to be 384/7kg of oil.