We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.
 
+0  
 
-1
258
1
avatar+1295 

Joe has 120 coins, all nickels and dimes. He has 20 more dimes then nickels.

 

a) Write a system of equations representing the scenario.

 

 

 

b) How many nickels and how many dimes does Joe have?

 Jun 7, 2018
 #1
avatar+99604 
+2

a) Let  D  be the number of dimes and  N be the number of  nickels

 

And we know that

 

D + N  = 120

N + 20  = D

 

b)  To solve this, sub  the second equation  in the first  for "D"  and we have

 

( N + 20 ) + N  =  120    simplify

2N + 20  = 120    subtract  20 from each side

2N  = 100      divide both sides by 2

N  = 50   = the number of  nickels

 

And N + 20  = D...so   

50 + 20   =  D =  70  =  the number of dimes

 

 

cool cool cool

 Jun 7, 2018

13 Online Users

avatar
avatar
avatar