Store A sells the refrigerator for P - P(0.15)
Store B sells the refrigerator for P - 150
Set the equations to equal and solve:
P- P(0.15) = P-150
Rewrite P(0.15) as 0.15P
P - 0.15P = P - 150
Subtract 0.15P from P:
0.85P = P-150
Subtract P from both sides:
-0.15P = -150
Divide both sides by -0.15:
P = -150 / -0.15
P = 1000
The original prices was $1,000
The sale price is 1000 - 150 = $850