Solution

This is a slightly difficult problem.
We know that Juan played in 4 games and struck out on an average of twice per game. Thus the total number of times Juan struck out was
4 x 2 = 8 times.
Let us assume that he struck out 'Z' times in the first game.
Since he struck out a total of 8 times, we write the equation as
number of strike outs: Z  +  0   +  0  +  0 =  8 times
game number:          (1st) (2nd) (3rd) (4th)   (total)

Thus we find Z = 8.
Hence Juan struck out 8 times in the first game