Irving has 10% as many quarters as nickels. If Irving has $5.25 in quarters and nickels, how many nickels does he have?
Total: 25q + 5n = 525 where q = number of quarters, n = number of nickels
Also: q = 0.1n number of quarters = 10% number of nickels (10% = 0.1)
Replace q in the first equation by 0.1n:
25*0.1*n + 5n = 525 or
2.5n + 5n = 525 or
7.5n = 525 so
n = 525/7.5 or
n = 70
There are 70 nickels.
ok it takes four quarters to make a dallor. then all you do is mulitply 5 to 4 which give you 21 quarters then mulitply it by 10 (in 10%) then divide by 5 (for the nickels). you get 4.20
Total: 25q + 5n = 525 where q = number of quarters, n = number of nickels
Also: q = 0.1n number of quarters = 10% number of nickels (10% = 0.1)
Replace q in the first equation by 0.1n:
25*0.1*n + 5n = 525 or
2.5n + 5n = 525 or
7.5n = 525 so
n = 525/7.5 or
n = 70
There are 70 nickels.
Irving has 10% as many quarters as nickels. If Irving has $5.25 in quarters and nickels, how many nickels does he have?
x = nickels ( 0.05 Cent)
y = quarters(0.25 Cent)
\(\small{ \begin{array}{rcll} $ 5.25 &=& $0.25 y + $0.05 x \qquad & | \qquad y = 10 \% \cdot x\\ $ 5.25 &=& $0.25 \cdot ( 10 \% \cdot x ) + $0.05 x \\ $ 5.25 &=& $0.25 \cdot ( \frac{10}{100} \cdot x ) + $0.05 x \\ $ 5.25 &=& \frac{$0.25 \cdot10}{100} x + $0.05 x \\ $ 5.25 &=& $0.025 x + $0.05 x \\ $ 5.25 &=& $0.075 x \\ $0.075 x &=& $ 5.25 \\ x &=& \frac{$5.25}{ $0.075 }\\ x &=& 70 \end{array} }\)
He has 70 Nickels and 7 Quarters.
70 * 0.05 + 7 * 0.25 = $5.25