Judging from the topic: the amount of work per person 1 hour 1/80.

Then:

The workload completed in the first 2 hours is 2*X* 1/80.

The engineering quantity completed in the last 8 hours is: 8*(X+5)* 1/80.

The equation is as follows:

2 * X * 1/80+8 *(X+5)* 1/80 = 3/4

2x+8x+40=60

x=2

Arrange two people first.