Q&A - P5 Math

[fohope]

Hi,
Could anyone help me on this problem? Thanks in advance.
From Nanyang CA 2013
The total values of 3 numbers A, B and C is 215. When the value of A is doubled, the value of B is decreased by 15 and the value of C is increased by 25, the values of the 3 numbers become the same. Find the value of A.

[zilojian]

Hi,
Could anyone help me on this problem? Thanks in advance.
From Nanyang CA 2013
The total values of 3 numbers A, B and C is 215. When the value of A is doubled, the value of B is decreased by 15 and the value of C is increased by 25, the values of the 3 numbers become the same. Find the value of A.

+++
Hello fohope,

Here is my working as below:-

A + B + C = 215 ---- Equation 1

2A = B - 15 ---- Equation 2
2A = C + 25 ---- Equation 3

++++

From Equation 2 and 3:-
B - 15 = C +25
B = C + 40 ---- Equation 4


Subsitute Equation 4 into Equation 1:-
A + B + C = 215
A + (C+40) + C = 215
A + 2C + 40 = 215
A + 2C = 175 ---- Equation 5


Subsitute Equation 3 into Equation 5:-
2A = C + 25 ---- Equation 3
2A - 25 = C

A + 2C = 175 ---- Equation 5
A + 2(2A-25) = 175
A + 4A - 50 = 175
5A = 225
A = 225/5
A = 45

Therefore, the value of A is 45.

Trust the above clarifies.

[Kangkangteo]

Hi,
Could anyone help me on this problem? Thanks in advance.
From Nanyang CA 2013
The total values of 3 numbers A, B and C is 215. When the value of A is doubled, the value of B is decreased by 15 and the value of C is increased by 25, the values of the 3 numbers become the same. Find the value of A.

A ---> 1u

B ---> 2u + 15

C -----> 2u - 25

A+B+C : 1u + 2u + 15 + 2u - 25 ----> 215

5u ---> 215 - 15 + 25 = 225

1u ---> 225/5 = 45

The value of A is 45.

[fohope]

Hi all,
Thank you for all your solutions.

[miki]

Appreciate some kind soul could tell me what is the exam format for P5 Maths CA2? Is it same as paper 1 since it is 50 minutes paper but calculator is allowed? Thanks in advance!

[bb_ mom]

Wouldn't the teacher have told the students? There's always paper 1 (MCQ) and paper 2. And I think only section B of paper 2 allows calculator.

[miki]

Thanks for the reply! I asked my kid and she said her teacher did not mention anything about the test format. Opps I forgot to mention that my kid is studying at Tao Nan.

[bb_ mom]

Just asked DS. Paper 1 comprises MCQ and short problem sums. No calculate. Paper 2 has short and long problem sums. Calculator allowed. I assume this is the PSLE format.

[Jerico]

Hi,

Can someone please help with the following problem :-

The ratio of the number of muffins Baker Tom baked to the number of muffins Baker John baked was 12 : 5 at first. Baker Tom baked more muffins and as a result, his muffins increased by 25%. How many more percent more must Baker John baked so that their total number of muffins baked would be equal in the end ?

Thank you in advance for your kind assistance.

[Jerico]

Hi,

Please help with the following question :-

Q : The sum of 2 fractions is 1-3/5. The difference between the 2 fractions is 2/3. What is the smaller fraction ?

Thank you !