Austin has pennies, dimes, and quarters. He has a total of $30.72. He has three times as many quarters as pennies and one-half as many pennies as dimes. How many of each coin does he have?

Answer 1

Let Austin has x pennies
He has 3x quarters and 2x dimes
3x (0.25) + x (0.01) + 2x (0.1) = 30.72
=> 0.96x = 30.72
=> x = 30.72/0.96 = 32
32 pennies, 64 dimes and 96 quarters are there with Austin