Q&A - P4 Math

[corneyAmber]

BigDevil:

:oops:


My eyes got stamp. Thought I saw 10G -> $10.50

No problem...For a moment I thought my eyes got stamp....kekeke. Thanks for clarifying.

[vsk]

ksi:

vsk:

Jim bought 3 goldfish and 4 swordtails and paid $8.10. He then bought 5 goldfish and 2 swordtails and paid $9.30. How much did he pay for goldfish ?.


Kindly help to resolve this. Thanks.

3G + 4S -> 8.10
[5G + 2S -> 9.30] x 2
10G + 4S ->18.60
(10-3)G -> 18.60-8.10
7G -> 10.50
G -> $1.50
8G -> 1.5 x 8 = $12

The gold fishes are $12.

Thank you very much KSI. Appreciate your help very much. :thankyou:

[hardeshis]

Mr Tan bought 5 kg of flour. He used 3/4 kg of it to bake some muffins and 7/8 kg of it to bake a cake. How much flour was left.

[Laura02]

hardeshis:

Mr Tan bought 5 kg of flour. He used 3/4 kg of it to bake some muffins and 7/8 kg of it to bake a cake. How much flour was left.

I think there must have been a typo error. 3/4 + 7/8 = more than 1. Probably the question reads and 7/8 of the remainder to bake a cake.

[hardeshis]

Laura02:

hardeshis:

Mr Tan bought 5 kg of flour. He used 3/4 kg of it to bake some muffins and 7/8 kg of it to bake a cake. How much flour was left.

I think there must have been a typo error. 3/4 + 7/8 = more than 1. Probably the question reads and 7/8 of the remainder to bake a cake.

ya may be..

[ttyh]

If 3 workers takes 6 days to complete painting a house, how many workers are needed if it needs 2 days to complete the job?

[tianzhu]

ttyh:

If 3 workers takes 6 days to complete painting a house, how many workers are needed if it needs 2 days to complete the job?

Hi

There are a few approaches.

A neat way is the use compound units.

Number of worker days to paint a house -------- 3*6 ------- 18

If it is 2 days, number of workers ------- 18/2 ------- 9

Best wishes

[little patrick]

Hi needs help to understand the question. Thanks in advance


There are 80 pupils in class A and class B. 4/9 of pupils in class A are boys and 3/5 of the pupils in class B are girls.

a) How many pupils are there in class A?
b) How many boys are there in both classes?

Ans (a) 45 & (b) 34

[MathIzzzFun]

little patrick:

Hi needs help to understand the question. Thanks in advance


There are 80 pupils in class A and class B. 4/9 of pupils in class A are boys and 3/5 of the pupils in class B are girls.

a) How many pupils are there in class A?
b) How many boys are there in both classes?

Ans (a) 45 & (b) 34

4/9 of pupils in class A are boys --> number of pupils in class A is a multiple of 9

3/5 of the pupils in class B are girls --> number of pupils is a multiple of 5

Total number 80 is a multiple of 5 --> number of pupils in class A is ALSO a multiple of 5 ie number of pupils in class A is a multiple of 5 and 9.
Smallest multiple of 5 & 9 --> 45

Number of pupils in Class A --> 45
Number of pupils in Class B --> 35
..with these, I think you can work out (b)

cheers.

[little patrick]

MathIzzzFun:

little patrick:

Hi needs help to understand the question. Thanks in advance


There are 80 pupils in class A and class B. 4/9 of pupils in class A are boys and 3/5 of the pupils in class B are girls.

a) How many pupils are there in class A?
b) How many boys are there in both classes?

Ans (a) 45 & (b) 34

4/9 of pupils in class A are boys --> number of pupils in class A is a multiple of 9

3/5 of the pupils in class B are girls --> number of pupils is a multiple of 5

Total number 80 is a multiple of 5 --> number of pupils in class A is ALSO a multiple of 5 ie number of pupils in class A is a multiple of 5 and 9.
Smallest multiple of 5 & 9 --> 45

Number of pupils in Class A --> 45
Number of pupils in Class B --> 35
..with these, I think you can work out (b)

cheers.

Hi , tks for your explain but I'm still not very understand the part 2 -> Total numer 80 is a multiple of 5 ......

if the question put in this way for (a) , find the number of pupils in Class B.

Does it means that I still need to find out the Class A number first 90-45=35 OR there is another way of finding the number of pupils in Class B without Class A number?

Tks