Tutor MathsGuru: Ask me for your burning Maths questions!

[Maths Monster]

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[Maths Monster]

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[zyberk]

Maths Monster:

Yes I have. Thanks for spotting my mistakes.

Day 1 = 5 - 2 = 3m
Day 2 = 3 + 5 - 2 = 6m
Day 3 = 6 + 5 - 2 = 9m
Day 4 = 9 + 5 - 2 = 12m
Day 5 = 12 + 5 - 2 = 15m
Day 6 = 15 + 5 = 20m

Thanks. That is the same answer my DD got. But her teacher insist that the answer is 7 days !

:x :x

[talk_aboutstudies]

Maths Monster:

talk_aboutstudies:

Is there a method where i can solve all speed questions like this:


A car and a van were travelling in opposite directions at speeds of 80km/h and 60km/h respectively. The car was travelling from Town A to Town B while the Van was travelling form Town B to Town A. At what time would the pass each other?


Note: No distance is given

Please help!

Time = Distance / (80 + 60) = Distance / 140

This is the same as assuming car speed is 140km/h and the time taken to travel from town A to B.

thanks!

[talk_aboutstudies]

Maths Monster:

talk_aboutstudies:

Is there a method where i can solve all speed questions like this:


A car and a van were travelling in opposite directions at speeds of 80km/h and 60km/h respectively. The car was travelling from Town A to Town B while the Van was travelling form Town B to Town A. At what time would the pass each other?


Note: No distance is given

Please help!

Time = Distance / (80 + 60) = Distance / 140

This is the same as assuming car speed is 140km/h and the time taken to travel from town A to B.

thanks!

[Herbie]

Dear All.

I have one qn below:

Fig 1 = 1 no. of cubes
Fig 2 = 4 no. of cubes
Fig 3 = 10 no. of cubes

How to create the formula to get the no. of cubes for fig 6?

Which figure will have 120 cubes?

Thanks!

[zyberk]

Herbie:

Dear All.

I have one qn below:

Fig 1 = 1 no. of cubes
Fig 2 = 4 no. of cubes
Fig 3 = 10 no. of cubes

How to create the formula to get the no. of cubes for fig 6?

Which figure will have 120 cubes?

Thanks!

[Vanilla Cake]

Herbie:

Dear All.

I have one qn below:

Fig 1 = 1 no. of cubes
Fig 2 = 4 no. of cubes
Fig 3 = 10 no. of cubes

How to create the formula to get the no. of cubes for fig 6?

Which figure will have 120 cubes?

Thanks!

Hi Herbie,
You need to post the picture that comes together with this 4-mark from Nanyang 2009 P6 SA1 Maths paper 2 Q15 set on 15 May 2009.
While waiting for Mathsguru's solution, pls refer to these helpful links for the solution:

http://psle2010a.blogspot.com/2010/03/mathsp62009sa1p2ny.html
http://www.onsponge.com/forum/35-thinkingmathonsponge/1917-p6-maths-2009-nanyang-sa1-paper-2.html

[adhdadhd]

ruyu:

Suzy bought 12 stickers from Singapura Bookshop. The price of each sticker was the same. If the price of 1 sticker was cheaper by 5-cents, she could have bought4 more stickers at the cheaper price. How much did she spend on 12 stickers?

cost per sticker = u cents.
total costs = 12u cents.

if cheaper by 5 cents, means each sticker cost (u-5) cents.
total costs = 16 x (u-5)= 16u - 80 cents.

Key to know: both the total costs remain the same,
12 u = 16u - 80
4u = 80
1u = 20

she spent 240 cents or $2.40 on 12 stickers.

[YLH88]

hi Mathsguru,


Need help in solving the following questions :

1) Sally and Joseph have an equal number of coins in their coin boxes. Every day, Sally takes out 5 coins and Joseph takes out 3 coins. When Sally finishes all her coins, Joseph still has 64 coins left. How many coins do they have altogether at first ?


2) At 2pm, a car travelled from Town A to Town B at an average speed of 80 km/h. At the same tme, a van travelled from Town B to Town A. After sometime, the car and van passed each other and were 20 km apart at 5pm. The car arrived at Town B at 7pm
a) Find the average speed of the van
b) What time did the van arrive at Town B ?


3) Celia wants to make as much tropical fruit shake as possible. The tropical fruit shake comprises of honey, strawberry and milk in the ratio of 1 : 3 : 7. She found that honey is sold at $1.50 per 100g, strawberry at $2 per 100g and milk at $1 per 100g. If she already has 900g of honey and $161 to spend,
a) find the amount of honey, strawberry and milk she can buy to maximize the amount of tropical fruit shake she can make.
b) How much money would she have left after buying honey, strawberry and milk ?


Thank you very much!