Question

Anna has a collection of 45 nickels and quarters worth $8.05. How many nickets does she have?

Answer 1

Anna has 16 nickels

Solution:

Let "n" be the number of nickels

Let "q" be the number of quarters

We know that,

1 nickel = $ 0.05 or 5 cent

1 quarter = $ 0.25 or 25 cent

Anna has a collection of 45 nickels and quarters

Therefore,

n + q = 45

q = 45 - n --------- eqn 1

Anna has a collection of 45 nickels and quarters worth $8.05

$ 8.05 is worth 805 cents

Thus we frame a equation as:

number of nickels x 5 cents + number of quarters x 25 cents = 805

$n \times 5 + q \times 25 = 805$

5n + 25q = 805 ----- eqn 2

Let us solve eqn 1 and eqn 2

Substitute eqn 1 in eqn 2

5n + 25(45 - n) = 805

5n + 1125 - 25n = 805

20n = 1125 - 805

20n = 320

n = 16

Thus Anna has 16 nickels