Answer:
number of large year book sold = 380
number of small year book sold =520
Step-by-step explanation:
Let the no. of large year book pages be x
given that
cost of 1 large year book = $4
cost of x large year book = x*cost of 1 large year book = $4x
Let the no. of small year book pages be y
given that
cost of 1 small year book = $2.5
cost of y small year book = y*cost of 1 large year book = $2.5y
also,
total year books sold were 900
no. of small year book + no. of small year book = 900
x + y = 900
y = 900 - x ------------------>1
also total money made by selling large and small year book = $2820
cost of x small year book + cost of x large year book = 2820
4x + 2.5y = 2820
using y = 900 - x in above equation
4x + 2.5(900-x) = 2820
4x + 2250 - 2.5x = 2820
1.5x = 2820-2250 = 570
x = 570/1.5 = 380
Thus,
number of large year book sold = 380
number of small year book sold = 900-380 = 520
