Lizzy: A jar on the family's counter contains change they've been saving a trip to the ice cream shop. There are 123 pennies, 85 nickels, 35 dimes, and a number of quarters. All five family members get a double scoop, which costs $3 each. After the trip, they have 48 cents left over. How many quarters were in the jar?.
Me: Hmmm, let me think. I think this is the detailed solution:
The family spent $15 on ice cream because 5 x 3 = 15. They total amount of change they had was $15.48 because 15 + .48 = 15.48. They have $1.23 in pennies because 123 x .01 = 1.23. They have $4.25 in nickels because 85 x .05 = 4.25. They have $3.50 in dimes because 35 x .1 = 3.5. Without the quarters they have a total of $8.98 because 1.23 + 4.25 + 3.5 = 8.98. They have $6.5 worth of quarters because 15.48 - 8.98 = 6.5. They have 26 quarters because 6.5 / .25 = 26. Final answer: 26.