
By: shirley wee (offline) Sunday, April 07 2013 @ 07:09 AM CDT (Read 631 times)



shirley wee 
Hi everybody! I'm stuck with this maths question. May you help me? Please show your working clearly.
Qn 1. There were dark chocolates and milk chocolates in a box. If 10 dark chocolates were removed from the box, the total number of chocolates left would be 6 times the number of dark chocolates left. If 30 milk chocolates were removed from the box, the total number of chocolates left would be 4 times the number of dark chocolates left. How many more milk chocolates than dark chocolates were there in the box?

Chatty
Registered: 02/28/12 Posts: 68





By: echeewh (offline) Sunday, April 07 2013 @ 07:12 PM CDT



echeewh 
hi Shirley,
Following pls find my worked solution:
***  for alignment purpose
<If 10 D were removed>
there would be (1/6)D and (5/6)M.
D 
M 
<before>
D <10> **************  1p + 10
M  ***  5p
<after  if 30 M removed>
there would be (1/4)D and (3/4)M
**< 1u >
D <10> ***************  1p + 10
M < 30 > **  5p  30
**< 3u >
From the <after> model, we have ...
1p + 10 = 1u
5p  30 = 3u
Rearranging these ...
1u  1p > 10  (1)
5p  3u > 30  (2)
(1)x3:
3u  3p > 30  (3)
(2)+(3):
5p  3p > 30 + 30
2p > 60
1p > 30
M  D (at first) = 5p  1p  10 = 4p  10
4p  10 > (4 × 30)  10 = 120  10 = 110
===========
Trust this helps.
Do let me know again if this is different from your Answerkey or if there's further clarification.
Cheers,
Edward

Active Member
Registered: 04/21/11 Posts: 627



