In a piggy bank, the number of nickles is 8 more than half the number of quarters. The value of the coins is $21.85. Determine the number of nickels.

Respuesta :

Answer:

The number of nickels is 47

Step-by-step explanation:

1 nickel is 5 cents while 1 quarter is 25 cents

let the number of nickels be n and the number of quarters be q

From the question;

the number of nickels n is 8 more than half the number of quarters (q/2)

n = q/2 + 8

(n-8) = q/2

q = 2(n-8) = 2n - 16 ••••(i)

let us convert $21.85 to cents

there are 100 cents in $1

Thus; $21.85 will be 21.85 * 100 = 2185 cents

1 nickel is 5 cents; so n nickels will be 5 * n = 5n cents

1 quarter is 25 cents; so q quarters will be 25 * q = 25q cents

The addition of both will give 2185 cents

Thus;

5n + 25q = 2185 ••••••(ii)

Substitute equation i into ii

5n + 25(2n-16) = 2185

5n + 50n - 400 = 2185

55n = 2185 + 400

55n = 2,585

n = 2,585/55

n = 47 nickels