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A road is paved at a certain time and speed. By the third quarter of the road, the paving plan was changed, the paving speed was increased by one eighth, and the daily paving time was reduced by one third. As a result, paving took 13 days. How many days is Wayne going to lie down?

This is it, right? The topic is unclear.

Got it for you.

Let the total amount be 1.

Lie down for x hours every day.

Leave it for y days

The original velocity is 1/xy.

Roads are paved at a certain time and speed.

Spread to three-quarters of the road.

The explanation accounts for three quarters of the total time.

That is to say, it takes three quarters of the total time, which is 3xy/4.

It takes x hours every day.

Total * * * needs 3xy/4x, which means 3y/4 days.

The amount of 1/4 remains.

The paving speed is increased by one eighth, that is, the original speed is multiplied by (1+8/ 1), that is, 9/8xy.

The daily laying time is reduced by one third, that is, the time multiplied by (1- 1/3) is 2x/3.

Remaining road time = remaining quantity/later speed, that is, remaining road time = 1/4 divided by 9/8xy =2xy/9.

Days spent on remaining roads = time spent on remaining roads/time spent every day thereafter, that is, days spent on remaining roads =2xy/9 divided by 2x/3.

That is, the number of days spent on the remaining roads =y/3.

Three-fourths days for paving this road+days for remaining roads = total days.

That is 3y/4+y/3= 13.

So y= 12.