Let us assume the number of times Bill saved $75 from his paycheck = x
Let us assume he number of times Bill saved $150 from his paycheck = y
Since he saved 75$ or 150$ for the 8 paychecks.
So, x+y=8
y=8-x (Equation 1)
Since Bill saved $825 from his last 8 paychecks using $75 or $150.
So, 75x+150y=825 (Equation 2)
Substituting the value of 'y' from equation 1 in equation 2,
[tex] 75x+150(8-x)=825 [/tex]
[tex] 75x+1200-150x=825 [/tex]
[tex] 75x-150x=825-1200 [/tex]
[tex] -75x=-375 [/tex]
x = 5
Therefore, Bill saved $75, 5 times from his paycheck.
