+0  
 
0
111
1
avatar

Janet spent 30% of her money on 7 cupcakes and 4 cookies on Monday. The cost of each cupcake was twice the cost of each cookies. She bought some more cupcakes and another 10 cookies with 6/7 of her remaining money on Tuesday. How many cupcakes did she buy on Tuesday?

 May 28, 2021
 #1
avatar+121065 
+1

Janet spent 30% of her money on 7 cupcakes and 4 cookies on Monday. The cost of each cupcake was twice the cost of each cookies. She bought some more cupcakes and another 10 cookies with 6/7 of her remaining money on Tuesday. How many cupcakes did she buy on Tuesday?

 

 

Let  the  amount  she  started  with  =  A

Let the  cost of a  cookie  =  C    and  the  cost of  a cupcake   =  2C

 

So

 

.30A  =  4C  +  7(2C)  ⇒   .30A  =  18C   ⇒   A  =  (18C)  / .30   =   60C   

 

So   she  had    .70A  left  after  spending  .30A   and   6/7  of this  =  (6/7) .70A =   .60A  = .60(60) C  =  36C

 

So  with  this   the   amount  she spent  on  cupcakes  on Tuesday  =

 

36C  -  10C    =     26C  =   13 (2C)

 

So...she  bought   13  cupcakes

 

 

cool cool cool

 May 28, 2021

38 Online Users

avatar