One quarter is equal to the 0.25 dollars and one nickel equal to the 0.05 dollars. The total number of quarter in the Sang-Jin's piggy bank is 41.
Given information-
Sang-Jin has only quarters and nickels in her piggy bank.
She has 66 coins in the bank with a value of $11.50.
One quarter is equal to the 0.25 dollars.
One nickel equal to the 0.05 dollars.
Let x be the quarter and y be the nickels.
As there is total 66 coins. thus,
[tex]x+y=66\\ y=66-x[/tex]
Suppose the above equation as the equation number 1.
As the total amount is $11.50. Thus,
[tex]0.25x+0.05y=11.50[/tex]
Put the value of y from the equations 1 in the above equation. Thus,
[tex]0.25x+0.05(66-x)=11.50\\ 0.25x+3.3-0.05x=11.50\\ 0.2x=11.5-3.3\\ x=\dfrac{8.2}{0.2}\\ x=41[/tex]
Thus the total number of quarter in the Sang-Jin's piggy bank is 41.
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