You have 64 coins, consisting of pennies, nickels, and quarters. the value of
the coins is $4.60. you also know that you have three times as many nickels as
quarters. find the quantity of each type of coin.

There are 20 pennies, 33 nickels and 11 quarters

Step-by-step explanation:

- You have 64 coins, consisting of pennies, nickels, and quarters

- The value of  the coins is $4.60

- Assume that there are p pennies, n nickles, and q quarters

∴ p + n + q = 64 ⇒ (1)

- Lets find the value of each types of coins

∵ 1 penny = 1 cent ⇒ p = p cents

∵ 1 nickel = 5 cents ⇒ n = 5n cents

∵ 1 quarter = 25 cents ⇒ q = 25q cents

∵ 1 dollar = 100 cents ⇒ $4.60 = 4.60 × 100 = 460 cents

∴ p + 5n + 25q = 460 ⇒ (2)

- You also know that you have three times as many nickels as  quarters

∴ n = 3q ⇒ (3) ⇒ the number of nickles by quarters

∵ 5n = 5(3q)

∴ 5n = 15q ⇒ (4) ⇒ the values of nickles by quarters

- Substitute (3) in equation (1) and (4) in equation (2)

∴ p + 3q + q = 64

∴ p + 4q = 64 ⇒ (5)

∴ p + 15q + 25q = 460

∴ p + 40q = 460 ⇒ (6)

- Subtract equation (5) from equation(6) to eliminate p

∴ 36q = 396

- Divide both sides by 36

∴ q = 11

- Substitute the value of q in equation (5)

∴ p + 4(11) = 64

∴ p + 44 = 64

- Subtract 44 from both sides

∴ p = 20

- Substitute the value of q in (3)

∴ n = 3(11) = 33

∴ n = 33

There are 20 pennies, 33 nickels and 11 quarters