Joel has twice as many cds as Mary has. Subtracting 7 from the number of cds Joel has and dividing by 3 equals the number of cds Blake has. If Blake has 25 cds, how many cds does Mary have?
j = 2m
(j-7)/3 = b
b = 25
start substituting:
(j-7)/3 = 25
j-7 = 75
j = 82
so,
m = 41
the number of CDs mariella has is 41
Let's break down the information given step by step to solve the problem:
1. Joel has twice as many CDs as Mary has.
Let's say Mary has x number of CDs. Therefore, Joel has 2x CDs.
2. Subtracting 7 from the number of CDs Joel has and dividing by 3 equals the number of CDs Blake has.
So, (2x - 7) / 3 = 25.
To find the value of x, we can solve the equation:
2x - 7 = 25 * 3,
2x - 7 = 75,
2x = 75 + 7,
2x = 82.
x = 82 / 2,
x = 41.
Therefore, Mary has 41 CDs.