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 By: Johny123 (offline)  Saturday, September 25 2010 @ 08:18 AM CDT (Read 2941 times)
Johny123

Can you tell me which of the two answers are correct and if its 960 cookies, why ?

Newbie

Registered: 09/25/10
Posts: 1

 By: kellywww (offline)  Monday, September 27 2010 @ 02:07 AM CDT
kellywww

Is this a P4 math question?

Junior

Registered: 12/31/06
Posts: 21

 By: tanhuimin (offline)  Tuesday, September 28 2010 @ 04:47 AM CDT
tanhuimin

This is a bit challenging for P4, should be able to solve via Model drawing

we can work backward to check the answer
check if the answer is 960,
no. of chocolate = 720, chocolate sold = 600, total sold = 600 + 210 = 810 --> 810/960 not = 4/5, so answer is definitely not 960.
check if the answer is 1200,
no. of chocolate = 900, chocolate sold = 750, total sold = 750 + 210 = 960 --> 960/1200 = 4/5 Bingo!

I have tried using what a P4 has learnt to solve the problem,
Pls refer to model diagram.

Thanks

Junior

Registered: 12/31/06
Posts: 18

 By: acelow (offline)  Friday, October 01 2010 @ 01:02 AM CDT
acelow

c = 3a (3 times of almond)

cx 5/6 + 210 = (c + a) x 4/5
3a x 5/6 + 210 = (3a + a) x 4/5
2.5a + 210 = 3.2a
210 = 3.2a-2.5a = 0.7a
a = 0.7 / 210 = 300

c=300x3=900
Sold = 900x5/6 + 210
750+210 = 960

A difficult question!

Newbie

Registered: 05/02/09
Posts: 14

 By: suz855 (offline)  Sunday, October 03 2010 @ 11:39 PM CDT
suz855

Before
chocolate = 6u
almond = 2u

After
1/5 --> 3u-210 ---- (1)
4/5 --> 5u+210 --- (2)

(1) x4 12u-840=5u+210
7u =1050, 1u=150

At first (8u) ---> 8 x 150 = 1200

Junior

Registered: 12/31/06
Posts: 16

 By: erne (offline)  Wednesday, October 13 2010 @ 02:52 AM CDT
erne

the question is :How many cookies did she sell?
So the Answer should be 1200x4/5=960

Newbie

Registered: 09/05/10
Posts: 2

 By: kellywww (offline)  Sunday, October 17 2010 @ 12:40 AM CDT
kellywww

if i am not wrong, it's a P6 math question.

Junior

Registered: 12/31/06
Posts: 21

 By: sethchew (offline)  Friday, October 22 2010 @ 08:52 PM CDT
sethchew

Quote by: Johny123

Can you tell me which of the two answers are correct and if its 960 cookies, why ?

well.......
3/4 x 1/6 = 1/8
1/5 - 1/8 = 3/40
210/3 = 70
70 x 40 = 2800
2800 x 4/5 = 2240
i'm sure its correct.
Look Checking:
2800 - 2240 = 560
if its correct, it should be 1/5th
560 x 5 = 2800
am i correct??

Junior

Registered: 10/22/10
Posts: 15

 By: sethchew (offline)  Friday, October 22 2010 @ 09:00 PM CDT
sethchew

Quote by: acelow

c = 3a (3 times of almond)

cx 5/6 + 210 = (c + a) x 4/5
3a x 5/6 + 210 = (3a + a) x 4/5
2.5a + 210 = 3.2a
210 = 3.2a-2.5a = 0.7a
a = 0.7 / 210 = 300

c=300x3=900
Sold = 900x5/6 + 210
750+210 = 960

A difficult question!

if you do not, check:
960(in your opinion) should be 4/5
960/4= 240 240x5= 1200
are you sure its correct?

Junior

Registered: 10/22/10
Posts: 15

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