16, both parties made the same parts. /kloc-After 0/6 days, Party A needs 64 B and 384 B to complete it. The work efficiency of Party B is 40% less than that of Party A, so how can we find the efficiency of Party A?

Solution: Let the working efficiency of A be A/ day, and then B be (1-40%)A = 0.6a/ day.

According to the meaning of the question

16a+64=0.6a× 16+384

16×0.4a=320

0.4a=20

A=50/day

A's work efficiency is 50/ day.

Arithmetic method:

B does 40% less than A every day.

Then 16 days is 384-64= 320 less.

Do 320/ 16 = 20 less every day.

Then the working efficiency of A = 20/40% = 50/ day.

17, Master Zhang has a rest every six days 1 day, and Master Wang has a rest every five days for two days. For an existing project, Master Zhang needs 97 days and 75 days. If two people cooperate, how many days does a project take?

Solution:

97 divided by 7 equals 13, leaving 6 13 * 6 = 78, 78+6 = 84 working days.

75 divided by 7 equals 10,5,10 * 5 = 50,50+5 = 55 working days.

Master Zhang completes 1/84 every working day and 6/84 =114 every week.

Master Wang completes 1/55 every working day and 5/55 =11/every week.

Two people work together to complete 139/4620 every working day and 25/ 154 every week.

Six weeks to complete 150/ 154, leaving 4/ 154.

(4/ 154)/( 139/4620)= 120/ 139

So, six weeks and one day, 43 days.

24. Two trains, A and B, leave relatively from AB at the same time. When they meet, the distance ratio between A and B is 4: 5. It is known that train B travels 72 kilometers per hour, and it takes 10 hour for train A to complete the whole journey. How many kilometers are there between AB and AB?

Solution: The ratio of the distance left when meeting is 4: 5.

Then the distance ratio is 5: 4.

The time ratio is equal to the inverse ratio of the distance ratio.

Distance ratio between Party A and Party B = 5: 4.

The time ratio is 4: 5.

Then it takes 10×5/4 = 12.5 hours for line B to complete the journey.

Then AB distance =72× 12.5=900 km.

25. Party A and Party B walk from A and B to each other at the speed of 4 kilometers and 5 kilometers per hour respectively. After meeting, they walked on. How many kilometers is there between A and B if A walks from the assembly point for another two hours and arrives at B?

Solution: The distance ratio when A and B meet = the speed ratio = 4: 5.

Then when they meet, A is 5/9 of the distance from the destination.

So AB distance = 4× 2/(5/9) = 72/5 = 14.4km.

26. Passenger cars and trucks depart from Party A and Party B relatively simultaneously. After meeting on the way, they moved on. They returned immediately after they arrived at each other's departure place. They met for the second time on the road. The distance between the two venues is120km. The bus travels 60 kilometers per hour and the truck travels 48 kilometers per hour. How many kilometers is the distance between Party A and Party B?

Solution: The speed ratio of passenger cars and trucks = 60: 48 = 5: 4.

Think of the whole distance as 1.

Then the first intersection is 1×5/(5+4)=5/9 from A.

The second encounter is three complete journeys.

Then the second intersection from B is1× 3× 5/9-1= 5/3-1= 2/3.

That is, the distance from A is 1-2/3= 1/3.

So the distance between Party A and Party B =120/(5/9-1/3) =120/(2/9) = 540 km.

for reference only