You can put this solution on YOUR website! a girl has 30 coins consisting of nickels and dimes amounting to $2.60.
how many coins of each kind does she have.
:
Let n = no. of nickels
Let d = no. of dimes
:
Write the no. of coins equation:
n + d = 30
n = (30-d); use this for substitution
:
Write the total value equation
.05n + .10d = 2.60
replace n with (30-d)
.05(30-d) + .10d = 2.60
1.5 - .05d + .10d = 2.60
-.05d + .10d = 2.60 - 1.50
.05d = 1.10
d =
d = 22 dimes
then
30 - 22 = 8 nickels
:
:
Check in the $ equation
.05(8) + .10(22) =
.40 + 2.20 = 2.60; confirms our solution
