Answer: jason has 10 dimes and 5 quarters.
Explanation:
The worth of a dime is 10 cents. Converting to dollars, it becomes
10/100 = $0.1
The worth of a quarter is 25 cents. Converting to dollars, it becomes
25/100 = $0.25
Let x represent the number of dimes that he has.
Let y represent the number of quarters that he has.
He has twice as many dimes as quarters. This means that
x = 2y
Jason has $2.25 worth of dimes and quarters. This means that
0.1x + 0.25y = 2.25 - - - - - - - - - - - 1
Substituting x = 2y into equation 1, it becomes
0.1 × 2y + 0.25y = 2.25
0.2y + 0.25y = 2.25
0.45y = 2.25
y = 2.25/0.45
y = 5
x = 2y = 2 × 5
x = 10