Just determine which pair of square numbers have a difference of 45. 9×9 - 6×6 = 45 Length of square B is 9 cm, hence the perimeter of square B is 36 cm.

thks thks. :)

Square a) 6x6 = 36 and square b) 9x9 = 81; gives a difference of 45cm. Square B has 4 sides of 9cm each, 4 x 9 = 36cm. P = 36cm

1/4 of book contained 50 pages (what was read on Saturday) The whole book contained 200 pages. 2/5 of book contained 80 pages (what was read on Sunday) 200 - 50 - 80 = 70 pages unread.

1/4 of book = 50 pages 1/4 x b = 50 b= 50 x 4 b= 200 Therefore book contains 200 pages Total read =1/4 + 2/5 = (5+8)/20 =13/20 Total pages Read = 13 x 200/20 =13 x 10 =130 Therefore pages unread = 200-130 =70

Xavier Sng... I also got the answer as 70... My question is 2/5 on Sunday... Is it 2/5 of the whole book or 2/5 of remaining pages(150pages) after reading on Saturday.. I find these type of QN is weird.. Does not state clearly..

Hola Izam, I have inferred that the question refers to 2/5 of the whole book.

1/4 of book = 50, therefore whole book has 200 pages. 200 pages divided by 5 = 40 pages, therefore 2/5 = 2 x 40 = 80 pages. 50 read + 80 read = 130 read. 200 - 130 = 70 not read/left to read. It would always be fraction of the whole book unless it stated otherwise. e.g. 'From the 'remaining pages' he read 2/5ths ... '

Tks

1/4 =5/20. 2/5=8/20.8/20+5/20 =13/20. 20/20=200 pages。200 pages-130 pages = 70 pages. Jedi.

150 - 5 - 5 - 7 x (28 - 10) = 14 cm (ans)

Thank you

thank u very much, yeo ;)

My pleasure. Thank you.

sorry yeo, i could not understand your steps :(

I start with end in mind. Since T will be 60% of S, I make S to end at 10u and T at 6u. Since T sold 104, I add 104 to 6u. Since S sold 1/3, the sold portion will be 5u (since left over is 10u).

A ratio approach.

Given that initially, the ration of T to S is 5:6, hence (6u+104)/15u = 5/6

thank u very much, yeo, i can understand your explanation!

thank u very much, xavier sng, your method is very clear, thanks

You are most welcome. Mister Yeo's model is a good one and it is worth learning the reasons on why he chose the number of units he used.

Alternatively, using the same model but changes the units to Xavier' illustration, works too. Easier also as no need to do too much calculation.

thanks sng n yeo for your help, very appreciated!

You are most welcome, Mavis. Regards. Thanks for the tag-team effort, Mister Yeo.

Xavier Sng why did you multiply the initial ratio by 5?

Hola Anupama. Nice name, and does it have a meaning or an interesting story of origin? Good question. Now we know that a third of the sausage buns was sold. So the number of units that represent the number of sausage buns initially should be divisible by 3. On top of that, in the final stage we are told that the remaining tuna buns were 60% or simply 3/5 of the remaining sausage buns. That makes it imperative that the final number of units of sausage buns be divisible by 5. Since the initial ratio of tuna buns to sausage buns is given to be 5:6, the "6" is divisible by 3 but not by 5. Hence I bumped the ratio up by 5 folds to make 30 divisible by 5 for the second stage of the calculation. I hope that helps.

Thanks Xavier Sng. Anupama means unique!

Arh....unique it is. Thank you.

Thank you so much Adrian Ng. Very clear visual steps. 👍🏻

Agreed