Kevin has 8 dimes and 5 quarters
Solution:
Let "d" be the number of dimes
Let "q" be the number of quarters
We know that,
Value of 1 dime = $ 0.10
Value of 1 quarter = $ 0.25
kevin had 13 coins in his pocket
Therefore,
number of dimes + number of quarters = 13
d + q = 13 ------ eqn 1
When he emptied his pockets kevin found he had $2.05
We frame a equation as:
number of dimes x Value of 1 dime + number of quarters x Value of 1 quarter = 2.05
[tex]d \times 0.10 + q \times 0.25 = 2.05[/tex]
0.10d + 0.25q = 2.05 ----------- eqn 2
Let us solve eqn 1 and eqn 2,
From eqn 1,
d = 13 - q ------- eqn 3
Substitute eqn 3 in eqn 2
0.10(13 - q) + 0.25q = 2.05
1.3 - 0.10q + 0.25q = 2.05
0.15q = 0.75
Divide both sides of equation by 0.15
q = 5
Substitute q = 5 in eqn 3
d = 13 - 5
d = 8
Thus there are 8 dimes and 5 quarters