Q&A - PSLE Math

[tianzhu]

whitety:

Hi,

I need help on this qn:

The ratio of Ann's salary to Ben's salary is 6:7. If Ann's salary is increased by 12%, by what percentage must Ben's salary be increased or decreased so that their salaries will be the same ?

Thanks!

Hi

You may work using MD or units.

To avoid with decimals, use equivalent ratios.

The ratio of Ann's salary to Ben's salary ----- 6:7 ------600:700

If Ann's salary is increased by 12%
600*1.12 ------ 672

We need to bring down Ben’s units from 700 to 672.

So, it’s s decrease of (700-672) ------ 28

28/700*100% ------4%

Hope this helps.

Best wishes

[tianzhu]

Winx5015:

Hi tianzhu,


Thanks for your solutions. Sorry to make you stress your eyesight. I tried to enlarge the image but don't know how to do it. (Will approach expert for advice )

As for Q(2), is from Fuchun Primary School SA1 2011 (Paper 2).

Have a nice weekends

Hi

I hope the answer is correct.

I can't resist the onslaught of old age, getting poorer eyesight is part of growing old.

It's an interesting question.

If you need more details, let me know, I'll try to prepare the slide.

Best wishes

[whitety]

tianzhu:

whitety:

Hi,

I need help on this qn:

The ratio of Ann's salary to Ben's salary is 6:7. If Ann's salary is increased by 12%, by what percentage must Ben's salary be increased or decreased so that their salaries will be the same ?

Thanks!

Hi

You may work using MD or units.

To avoid with decimals, use equivalent ratios.

The ratio of Ann's salary to Ben's salary ----- 6:7 ------600:700

If Ann's salary is increased by 12%
600*1.12 ------ 672

We need to bring down Ben’s units from 700 to 672.

So, it’s s decrease of (700-672) ------ 28

28/700*100% ------4%

Hope this helps.

Best wishes

Hi tianzhu,

Thank you very much for your help!

[tianzhu]

whitety:

Hi tianzhu,

Thank you very much for your help!

Hi

You're welcome.

Best wishes

[tianzhu]

Chenonceau:

tianzhu... :thankyou:

Hi

You're welcome.

Best wishes

[Michaelia0816]

Lestercity and Macity are 108 km apart. The motorist travelled from Lestercity to Macity at 100km/h while a jogger jogged from Macity to Lestercity at 10km/h. If the jogger started off 2 hours earlier than the motorist, how far had the motorist to travel before meeting the jogger along the way?


Do help me with the question, step by step pls

[tianzhu]

Michaelia0816:

Lestercity and Macity are 108 km apart. The motorist travelled from Lestercity to Macity at 100km/h while a jogger jogged from Macity to Lestercity at 10km/h. If the jogger started off 2 hours earlier than the motorist, how far had the motorist to travel before meeting the jogger along the way?


Do help me with the question, step by step pls

Hi

In 2h, the jogger covered 2*10 ------20km

108 – 20 ------ 88

In 1h, the motorist and jogger covered a combined distance of 110 km (100+10)

88/110------ 4/5h or 0.8h

The motorist had to travel 4/5*100 ----- 80km

Best wishes

[Michaelia0816]

Oh Tianzhu, thank! I still got 40 question to complete.

[Michaelia0816]

Tianzhu, I need some calculation help, friends here may help too!

A)60km divide 42km/h = 1h_?_min
B)60km divide 56km/h = 1h?__min

[jewelbox]

Many thanks to atutor2001, Zack7, ADoc and Tianzhu for teaching me how to solve circle and rect/sq overlapping qns on 4 Apr pg554. :udaman: Ive been busy n didnt get to look at the solns till now. I know how to do already. :rahrah: Thank you so much. :boogie: