90#2=45 boxes
90#5= 18 boxes
Answer: If one is packed in every two cases, it can be packed completely. If it is packed in five boxes, it can also be packed accurately. Because 90 is divisible by 5.
There are 57 balls in the sporting goods store, and every three balls are packed in a box. Can they be properly packed?
57#3+ 19 cases
Answer: I can just finish it.
3: A and B type a document of 10000 words, A type 1 15 words per minute, and B type 135 words per minute. How many minutes will it take?
10000 # (115+135) = 40 points.
Answer: It can be finished in 40 minutes.
4. Grade five students plant trees, 13 or 14. Each group has just finished. How many students took part in planting trees in grade five?
13X 14= 192 people
Answer: At least 192 people participated in tree planting in the fifth grade.
Although the following questions belong to practical problems, they are related to equations. I solved it with equations.
5: Two cars go back and forth from one place. One car has a speed of 365,438+0 kilometers per hour, and the other car has a speed of 44 kilometers per hour. How many minutes later, the two cars are 300 kilometers apart?
Equation:
Solution: Two cars meet after X point.
3 1X+44X=300
75X=300
X=4
4 hours =240 minutes
Answer: After 240 minutes, the distance between the two cars is 300 kilometers.
6: Two engineering teams will excavate a tunnel with a length of119m, and two teams will carry out construction from both ends. Team A digs 4 meters every day, while Team B digs 3 meters every day. How many days does it take to dig the tunnel?
Solution: Set X days to dig tunnels.
3X+4X= 1 19
7X= 1 19
X= 17
Answer: 17 days, the tunnel was dug.
7. School chorus and dance team 140 people. There are six times as many people in the chorus as in the dance team. How many people are there in the dance team?
Solution: There are X people in the dance team.
6X+X= 140
7X= 140
X=20 people
A: There are 20 people in the dance team.
From here on, this is not an equation problem.
8. The two brothers walked from home to the gym at the same time, with a length of 1300m. My brother walks 80 meters per minute, and my brother rides his bike to the gym at a speed of180 meters per minute, and will be right back. On the way, he met his brother. How many minutes did my brother walk?
1300x2 = 2600m 2600#( 180+80)
=2600#260
= 10 point
Answer: At this time, my brother left 10 minutes.
At 9 o'clock on Children's Day, Mr. Wang bought 360 biscuits, 480 sweets and 400 fruits, made a beautiful gift package and distributed it to the children as gifts. How many gift packages can he make at most?
360+480+400= 1240
Answer: You can make at most 1240 small gift packages.
10: Naughty bought 40 balloons and invited his classmates to blow them at home. In order to share the balloons equally, how many students should be invited to blow them? Naughty not to participate.
40#2=20 people 40#4= 10 people 40#5=8 people.
40#8=5 people 40#@0=4 people 40#20=2 people.
A: There are six ways to invite students, namely: 20, 10, 5, 8, 4 and 2.