The answer is B. He is incorrect because he should have only 5 factors of 3.
1 quarter = 25 cents.
1 dime = 10 cents.
3 quarters = 3*25 = 75 cents.
10 cents = 1 dime.
75 cents = 75 / 10 dimes
= 7.5 dimes.
Therefore 3 quarters equal 7.5 dimes.
9w - 7 = 5
9w= 5+7
9w=12
w= 4/3 or 1.33
