A car from a to B, if 36 kilometers per hour, 8 hours to reach, the car at 36 kilometers per hour after a period of time, because it took 15 minutes to line up to refuel, in order to be able to arrive in B within 8 hours, after refuelling, must travel 7.2 kilometers per hour, how many kilometers from the gas station to B?

A car from a to B, if 36 kilometers per hour, 8 hours to reach, the car at 36 kilometers per hour after a period of time, because it took 15 minutes to line up to refuel, in order to be able to arrive in B within 8 hours, after refuelling, must travel 7.2 kilometers per hour, how many kilometers from the gas station to B?

The whole journey is 36 * 8 = 288km
In addition to refueling, it took 8-15 / 60 = 31 / 4 hours
Suppose you've been driving at 36 km for X hours
36x+（36+7.2）*（31/4-x）=288
36x+334.8-43.2x=288
x=6.5
So after a period of time, we drove 36 × 6.5 = 234 km
So 288-234 km from gas station to Yidi is 54 km
15/60*36=9
9/7.2=1.25
1.25*(36+7.2)=54
The gas station is 54 kilometers away from B

The master and the apprentice process 168 parts in total. It takes 5 minutes for the master to process one part and 9 minutes for the apprentice to process one part. How many parts do they process when they finish the task?

According to the meaning of the question, we get X: 15 = (168-x): 19, & nbsp; 19x = (168-x) × 15, & nbsp; 19x = 33.6-15x, & nbsp; 1445x = 33.6, & nbsp; & nbsp; & nbsp; & nbsp; X = 33.6 × 4514, & nbsp; & nbsp; & nbsp; & nbsp

It takes 8 hours for the master to make a batch of parts, and 10 hours for the apprentice to do it alone. Now the two work together for 126 parts in an hour

Master 1 hour to do 1 / 8 of the total parts, apprentice 1 hour to do 1 / 10 of the total parts
Suppose there are x parts in this batch
（1/8+1/10）*X=126
X=560

126. Master and apprentice work together to process a batch of parts, and finish 3 / 5 of the batch in 3 hours. Master processes 60 parts per hour, apprentice
1. Master and apprentice work together to process a batch of parts. The master who finished the batch of parts in 3 hours processes 60 parts per hour, and the apprentice works alone in 12.5 days. How many parts can I ask for?

After finishing this batch of parts in 3 hours, the master processed 60 pieces per hour, and the apprentice did it alone for 12.5 days
Is the unit hour or day?
If the unit is an hour
Suppose the apprentice does x every hour
Then 3 (60 + x) △ 3 / 5 = 12.5x
x=40
40 × 12.5 = 500
A: there are 500 parts in this batch