+0  
 
0
286
3
avatar

Irving has 10% as many quarters as nickels. If Irving has $5.25 in quarters and nickels, how many nickels does he have?

Guest Nov 17, 2015

Best Answer 

 #2
avatar+26322 
+10

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.

Alan  Nov 17, 2015
Sort: 

3+0 Answers

 #1
avatar+79 
+4

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

Mathkid  Nov 17, 2015
 #2
avatar+26322 
+10
Best Answer

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.

Alan  Nov 17, 2015
 #3
avatar+18712 
+10

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

 

laugh

heureka  Nov 17, 2015
edited by heureka  Nov 17, 2015
edited by heureka  Nov 17, 2015

4 Online Users

avatar
avatar
avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details