Question

Marcy has a total of 100 dimes and quarters. If the total value of the coins is $14.05, how many quarters does she have? Use a system of equations to answer

Answer 1

Let

x

be the number of quarters, and

y

be the number of dimes.

x

+

y

=

100

0.25

x

+

0.10

y

=

14.05

Solve by substitution:

y

=

100

−

x

∴

0.25x + 0.10(100 - x) = 14.05#

0.25

x

+

10

−

0.10

x

=

14.05

0.15

x

+

10

=

14.05

0.15

x

=

4.05

x

=

27

Solve for

y

now:

y

+

27

=

100

y

=

100

−

27

y

=

73

Hence, Marcy has

27

quarters and

73

dimes.

Hopefully this helps!

Explanation:

Answer 2

So she has $10 worth of dimes because 100*.10 = $10 so you subtract 10 from 14.05 which is 4.05. There is 4 quarters in a dollar. So 4*4 is 16.

She has 16 quarters
100 dimes
1 nickel