Q&A - PSLE Math

[MathIzzzFun]

shurley197323:

Thanks MathIzzzFun. Because her teacher advised my girl not to use the guess & check method.

Hi shurley197323

you are welcome :lol:



cheers.

[jieheng]

Hifive:

Hi jieheng

Thanks for your explanation.

Regards

Hi Hifive ,

You are welcome .

Regards,

[tianzhu]

jesschan:

Got it! Thanks, Tianzhu.

Hi jesschan

Good Morning.

You're welcome.

Best wishes

[Jcong]

Can u pls help me solve this maths problem?


The ratio of the mass of chicken to the mass of fish was 3:5. 16 kg of the fish was sold to customers. After that, the ratio of mass of chicken to the mass of fish was 7:9. Find the mass of fish at first.

[chl72]

Need help in this, if the number of girls is 20% of the boys, how many percent more are the boys than girls? Thanks!

[chl72]

Jcong:

Can u pls help me solve this maths problem?


The ratio of the mass of chicken to the mass of fish was 3:5. 16 kg of the fish was sold to customers. After that, the ratio of mass of chicken to the mass of fish was 7:9. Find the mass of fish at first.

Let me try.

At first,
C : F
3 : 5
(x7) (x7)
21 : 35

After 16kg fish sold,
C : F
7 : 9
(x3) (x3)
21 : 27

35U - 27U = 8U
8U -> 16kg
1U -> 2kg
35U -> 70kg

70kg of fish at first. Right?

[elkniwt]

Hi chl72,


Girls = 20%
Boys = 100%
So Boys are (100 - 20 80% more than the girls.

[jieheng]

chl72:

Need help in this, if the number of girls is 20% of the boys, how many percent more are the boys than girls? Thanks!

Girls 20%

Boys 100%

Percent of more boys than girls are = (100% - 20%) / 20% * 100% = 400 % (Ans)

When solving the percentage question ,

To compare the percentage of A to B (A more than B or A less than B) ,

The percentage =[ (A - B) / B ]* 100 %

[Jcong]

What I don’t understand why you X7 at first and X3 for the scond ratio? I apologise for not being very clever.

[jojo]

Jcong:

What I don't understand why you X7 at first and X3 for the scond ratio? I apologise for not being very clever.

May i know, this is for Primary X???