Hope it helps.

$67.75kg ?

A=4B 4B-52.5=(B-10.15)/2 8B-105=B-10.15 B=13.55 A=54.2

M=20-N 3N=2M=2*(20-N)=40-2N 5N=40 N=8

M=20-N=12

n+m= 20 n+n+n = m+m Double first statement: n+n+m+m = 40 Replace m with n: n+n+n+n+n = 40 n = 40/5 = 8 m = 20-8 = 12

With or without symbolic algebra? The pair of simultaneously equations can be written as: N + M = 20 ---- Eqn 1 3N = 2M ----- Eqn 2 Multiplying Eqn 1 by 2, we obtain 2N + 2M = 40 ---- Eqn 3 Since 2M = 3N, we have 2N + 3N = 5N = 40. So, N = 8. M = 12.

Thanks all. This is a p2 math. Had prob trying to put it into equation. Appreciate all your help. :))

For p2, have to use simple method. The one I wrote should be suitable.

Joyce Quek, it will be good to post the original question because sometimes the context of the question can allow for alternative solutions. The question in its current form is definitely not a P2 question. :)

Thanks Lay Koon. I have explained to my nephew. He is able to understand with your solution. Sorry, Ban Heng. My mum copied the question from my nephew's p2 worksheet as he has returned it to his teacher. I should have stated it as a p2 qn initially. Will take note next time.

Too chim for P2...

P2???

Indeed, Connie. My hub had the ans but do not know how to explain in equations.

Joyce for p2 they need to solve this by model drawing instead of algebra. It's a bit difficult and don't look like a p2 question to me.

Joyce Quek, I am just curious. Is this question written in this form, as in M + N = 20 etc.? Also, is it meant as an enrichment or a worksheet? If it is a worksheet, this question (in its current form) is not age appropriate.

Cindy, I think Lay Koon's method is acceptable for his level. Ban Heng, my mum told me it's his worksheet. It's my nephew's work so I'm not v sure either. But really appreciate all your help.

8

N+M = 20 N =20-M (20-M)+(20-M )+(20-M)=m+m 60-3m = 2m 5m = 60 m =12 n=8

Irin Lau Sandy Goh Edde Elaine Autum Juliet

I personally think P2 shd use number bonding, 2 + 18, 3 +17, 4+16.... sure can get the answer, bcos not all children can used algebra.

For P2, they should be using guess and check method

Joyce Quek, I actually agree with Starfruit Cindy. Lay Koh Lay Koon's method is basically still symbolic algebra, albeit a more acceptable version for mathematically inclined P2 students. Even with a model method solution, I still feel that this question (written in its current form) is not appropriate. Here's a model method solution, which basically mirrors the algebraic solution. I think Eunice Tee's suggestion to use number bonds and then guess and check the two numbers is the most age-appropriate solution for a P2.

Seriously is for P2?

M is 10

20/3

6.75

Actually my sons were able to view the problem in this manner when they were in p2 and p3, using observation. In fact, they surprised me when they used this method.

Guess and check method

I remember they used to have problems with moon and star pictures. Similar to this problem but no alphabets, only pictures.

Childrens are smartest when they are age 0-11. The p6 is for stress management theory.

Thanks for all yr time and effort helping to solve the math problem. I certainly learnt a lot today.

M=20-N N+N+N=20-N+20-N 5N=40 => N=8 => M=20-8 =>M=12

N=8, M=12

N+M =20 3N=2M N=2/3M 5/3M=20 M=60/5=12 N=20-12=8

N =8 M =12

Why double the pieces to get 40?

N=8 M=12

Depending on the calculation method and greek numeric study.

8 and 4.

Sorry 12 n 8.

Solution made Visual :P

Thanks

Hiz. Why one of them has to remain constant?😧

Zhong Shu Hao

this proportion is by common sense actually. more chefs, means more food, so more ppl can eat. more time, so more food can be cooked, so more ppl can eat.

keeping one of the constant is to lessen confusion.

This likely to b psle qn? Have not come across in past year papers.

if this is a PSLE Q, then working would be the one I have posted. If is a Sec Sch Q, then working would be different, and much more simple.

Thanks.