Yes there is a formula call Gauss Theorem.

1 + 99 = 100 -2 - 98 = -100 => 100 - 100 = 0 3 + 97= 100 -4 - 96 = -100 => 100 - 100 = 0 There are 99 numbers so only 1 number will be left after all the other number knock off each other. It is 50 ((99+1)/2). Do take note that all even numbers are negative and odd number are positive. Therefore the amount that is left is -50.

A:B-> 7:17(24u) C:T. 1:9--->. A+B=9u-1u=8u C:T: 1:9-->. 3:27 (A+B->24u) A:B:C: 7:17:3. (27u total).. Can solve from here!?

(A+B)- C -> 5.25litres 24u-3u-> 5.25 litres 21u->. 5.25 u-> 0.25 Find B-> 17u

Thanks

Hi, Ida! There is a hint for part a. Which is lesser: flour or rice? Once you know which is lesser, you can find the mass of the flour. For part b, use part a answer to add to the mass of rice to get the total mass. :)

Shaoyang Brandon, Hariani Salleh...thx alot ya!!

a) 36green marbles 18 red marbles b) 22 (this is the ans my girl get)

Ivy Tan....thx u ya!

Hi LadyMummy Ida. You can solve this problem from two approaches. First, draw 1 unit of red marbles. Then, for the red marbles model, draw the additional 7 marbles beside it. Multiply this new model by 2 for the green marbles. You will get 2 units + 14 marbles. Then, refer to the other image below for the model. Solution is within the model. :)

The second approach is to start from two units of green marbles and one unit of red marbles. Then, remove 25 from green, 7 from red. You will still end up with the same model. :)

Shaoyang Brandon...hey...thanks alot...much clear for my son.

Hariani Salleh...thank u ya!

Hi, since there were equal green and red left in the end, then the difference between green and red at first was the same as the difference between the removed green and red. At first: Difference: 1u = 25-7 = 18 Green: 2u = 18×2 = 36 Total: 3u = 36+18 = 54 End total: 54-25-7 = 22

Teo Kai Meng....thank u ya!!

Not at all

Welcome!

561 ÷ 3 gives you the middle of the 3 pages. +1 gives the last and -1 give you the other page