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.