There are 21 nickels in carol bank
Solution:
Given that Carol's piggy bank consists of quarters and nickels
There are $ 4.55 in total
Let "a" be the number of nickels in bank
Let "b" be the number of quarters in bank
We know that,
1 quarter = $ 0.25
1 nickel = $ 0.05
Given that there are seven more nickels than quarters
Number of nickels = number of quarters + 7
a = b + 7 ---- eqn 1
From given question,
number of nickels in bank x value of 1 nickel + number of quarters in bank x value of 1 quarter = $ 4.55
[tex]a \times 0.05 + b \times 0.25 = 4.55\\\\(b + 7) \times 0.05 + b \times 0.25 = 4.55\\\\0.05b + 0.35 + 0.25b = 4.55\\\\0.3b = 4.55 - 0.35\\\\0.3b = 4.2\\\\b = 14[/tex]
Therefore from eqn 1
a = b + 7 = 14 + 7 = 21
a = 21
Thus there are 21 nickels in carol bank
