Lois has 10 coins in quarters and dimes in their pocket. After counting, the total value is $1.45. How many of each coin did Lois have?
Let the number of quarters =x and the number of dimes = 10 - x
So
Value of a quarter * their number + value of a dime * their number = 1.45
.25 x + .10 (10 -x) = 1.45 simplify
.25x + 1 - .10x = 1.45
,25x -.10x = 1.45 - 1
.15x = .45 divide both sides by .15
x = 3 = the number of quarters
10 - x = 10 - 3 = 7 = the number of dimes