Q&A - P3 Math

[CoffeeCat]

cathycho:

What is the fastest way to do this sum?


Find the sum of 18+20+22+........+36+38+40

Hi, notice that there is a pattern in the numbers, which led to the insight that 18+ 40 = 20 + 38 = 22 + 36, i.e. one can distribute the numbers evenly.
so the average will be (18+40)/2 = 29
And there are 12 such terms, total will be 12*29 = 348

The standard formula is total = average * no. of terms

[cathycho]

Thks, CoffeeCat.

[lydia_chin]

Can someone help with this sum?


Susan had twice as many stamps as Lisa. After Susan gave away 120 stamps to her brother and Lisa gave away 48 stamps to her friend, they had an equal number of stamps.

How many stamps does Susan had at first?

[BigDevil]

http://i47.tinypic.com/2j10b2g.jpg\">

[lydia_chin]

:thankyou: BigDevil!

[imacsg]

Can someone help me the below question?

Henry has some apples, when he puts them equally into boxes of 3 he will need 5 more boxes than if he put them into boxes of 4. How many apples does he have?
Thanks.

[MathIzzzFun]

imacsg:

Can someone help me the below question?

Henry has some apples, when he puts them equally into boxes of 3 he will need 5 more boxes than if he put them into boxes of 4. How many apples does he have?
Thanks.

Hi

http://postimage.org/image/cdfynp3qf/

cheers.

[imacsg]

Hi,

Thanks for your prompt reply.

[SAHM Chew]

Please help


A square carpet covers 7/8 of the floor. What is the area of the uncovered floor if the carpet has a side of 7m?

Thanks

[tianzhu]

SAHM Chew:

Please help


A square carpet covers 7/8 of the floor. What is the area of the uncovered floor if the carpet has a side of 7m?

Thanks

Hi

Area of square carpet ------ 7*7 ------- 49

7 units ------- 49

1 unit -------- 7

Area of uncovered floor ------- 1/8 ------ 1 unit ------- 7

Best wishes