Note that 1/100 + 99/100 = 1; 2/100 + 98/100 = 1; 3/100 + 97/100 = 1; and so on. 1. You need to "count" how many such pairs. 2. The last pair is 49/100 + 51/100, and so there are ... pairs. 3. Plus the 50/100 that is not accounted for. :)

thanks

So should be 99 ?

1/100 to 49/100 + corresponding 99/100 to 51/100 = 49 pairs = 49. Take whole number 49 + 50/100 (0.5) = 49.5

Thanks Sharon !

Hi! I think since Tom can assemble half of a toy when Jerry can only assemble a quarter means that Tom can assemble a toy twice as fast as Jerry. So, if Tom assembled a fifth of a toy, Jerry had only assembled half of what Tom had, thus, Jerry had assembled half of a fifth which is a tenth. I hope my answer helps.. :)

Agreed w Jojo

Hi, can share what level this is ? Thanks

Hope this helps.

I'd say 1/10.

Hi, Stella Cheong! It's from P6.

Thanks everyone for your guidance.

Thanks Suzzie Toh

Awesome. :-)

Thank you!!!

Why am I still using algebra!!! Urghh...

10 teams. 1st team = 9 matches; second team play 8 matches; third team 7 matches...............10th team 0 match. Thus Total matches = 9+8+7+6+5+4+3+2+1 = 45 matches.

I got 45 too. So it's simply by counting and adding. No models, tables or formulae?

This is quite direct. Solve quite fast. Use simple ways to solve and save time. Don;t need model. As every team will play with other teams. But in decreasing number in order to avoid repetition. This is the way to solve i believe. Fast and simple :)

Can draw diagram to illustrate understanding...

Agree with all above methods. But is it not easier to consider tt there are 5 matches each round, and since each team needs to play agst 9 other teams, so total there are 9 rounds. Answer will be 5 x 9 = 45

Adding 1+2+3........9 can be done with adding it AGAIN. 1+9..2+8..3+7.....giving 10x9=90. But this must be halved...giving45. Einstein used this method of adding a series...

It does introduce a series. Good example. A plays 9 games...B plays 8 (its. Game with A has been added) and carry on...then introduce the einstein trick! Kids will love it!