Question

Melissa keeps a jar for holding change. The jar holds 21 coins. All of the coins are quarters and nickels. The total amount in the jar is $3.85. How many quarters are in the jar?

Answer 1

A) n + q = 21
B) .05n + .25q = 3.85
Multiplying A) by -.05
A) -.05n + -.05q = -1.05 then adding this to B)
B) .05n + .25q = 3.85
.20q = 2.80
q = 14 quarters
n = 7 nickels

Check
14q + 7 n = 21 coins
14*.25 = $3.50
7*.05 = $.35
Correct!!!

Answer 2

about 15 coins are quarters