Answer: 90x + 25
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Work Shown:
1 dime = 10 cents
x dimes = 10x cents
1 nickel = 5 cents
(x+5) nickels = 5(x+5) = 5x+25 cents
1 quarter = 25 cents
3x quarters = 25*3x = 75x cents
total = dimes + nickels + quarters
total = (10x) + (5x+25) + (75x)
total = (10x+5x+75x) + 25
total = 90x + 25 cents
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An example:
Let's say x = 12
- x dimes = 12 dimes = 12*10 = 120 cents
- x+5 nickels = 12+5 = 17 nickels = 17*5 = 85 cents
- 3x quarters = 3*12 = 36 quarters = 36*25 = 900 cents
total = 120+85+900 = 1105 cents = $11.05
also,
total = 90x+25 = 90*12+25 = 1105 cents = $11.05
Divide by 100 to go from cents to dollars.