Welcome to Test-paper.info
Saturday, February 24 2018 @ 03:51 PM CST
 Select a Forum » General Chat » Primary 1 Matters » Primary 2 Matters » Primary 3 Matters » Primary 4 Matters » Primary 5 Matters » Primary 6 Matters » Question, Feedback and Comments » Education Classified
 Forum Index >  Test Paper Related >  Primary 5 Matters Pri 5 Maths ACS problem sum
 | Printable Version
 By: jennefer_06 (offline)  Wednesday, April 11 2012 @ 11:13 AM CDT (Read 1883 times)
jennefer_06

Help needed for this question.

Grandma had some yellow and purple sweets in the ratio of 9:7. On monday, she made 54 more yellow sweets. On Tuesday, she gave away 44 purple sweets and sold 129 yellow sweets. The number of yellow sweets to the number of purple sweets became in the ratio of 6:5. How many yellow sweets are there in the end?

Newbie

Registered: 03/19/12
Posts: 3

 By: MathIzzzFun (offline)  Thursday, April 12 2012 @ 01:45 AM CDT
MathIzzzFun

Hi

solution attached - http://tinyurl.com/7934dg6

cheers.

Chatty

Registered: 04/02/10
Posts: 36

 By: echeewh (offline)  Thursday, April 12 2012 @ 05:52 AM CDT
echeewh

Hey Jennefer,

In addition to MathizzzFun's solution using Cross-Multiply method ( a very similar method to that used in OnSponge - Conquer Problem Sums ), one other method is the Simultaneous method ( aka Compare & Replace / Elimination method ).

This is it ....

Number of Yellow (Y) sweets sold by Tuesday = 129 - 54 = 75

Y : P
9 : 7

-75 - 44

6 : 5

Since the before and after unit qty are different, we denote this by unit (u) and part (p) for before and after respectively as follows:.

9u - 75 = 6p
7u - 44 = 5p

Rewriting the above, we have:

9u - 6p = 75 ----- (1)
7u - 5p = 44 ----- (2)

As the question is interested in finding the yellow sweets at the end (which is the part (p) qty ), we shall eliminate the unit (u) qty as follows:

(1) x 7: 63u - 42p = 525 ----- (3)
(2) x 9: 63u - 45p = 396 ----- (4)
(3) - (4): -42p + 45p = 525 - 396
3p --> 129
1p --> 43

Number of Yellow sweets at the end = 6p --> 6 x 43 = 258

==================================================

Trust the above technique helps.

Cheers,
Edward

Active Member

Registered: 04/21/11
Posts: 627

 All times are CST. The time is now 03:51 pm.
 Normal Topic Locked Topic Sticky Topic
 New Post Sticky Topic w/ New Post Locked Topic w/ New Post
 View Anonymous Posts Able to Post HTML Allowed Censored Content