Answer: 172
Step-by-step explanation:
Mystery Science Fiction Biographies
4x 3x
4y 5y
Science Fiction = 48
3x = 48 ⇒ x = 16
4y = 48 ⇒ y = 12
Mystery: 4x = 4(16) = 64
Biographies: 5y = 5(12) = 60
Mystery + Science Fiction + Biographies = Total
64 + 48 + 60 = Total
172 = Total