A factory produced 480 A and B machines in the first quarter, and plans to produce 554 A and B machines in the second quarter after improving the production process.

Suppose that in the first quarter, the factory produced two kinds of machines, A and B, X and Y respectively.

According to the meaning of the question

The factory produced 480 machines A and B in the first quarter, and obtained

X+Y = 480 ( 1)

After improving the production process, it is planned to produce 554 sets of these two machines in the second quarter, in which the output of machine A is increased by 10% and that of machine B is increased by 20% compared with the first quarter. It can be concluded that

x *( 1+ 10%)+Y *( 1+20%)= 554(2)

Transform (1) into X=480-Y, and then substitute it into (2).

(480-Y)* 1. 1+ 1.2y = 554

The solution is Y = 160.

Then X = 480-Y = 480- 160 = 320.

So 320 units were produced in the first quarter, 160 units.