840-240=600(50%ruler and 75%eraser) 600x2=1200(100%ruler and 150%) 1200-840=360(50% rulers) By now you should of figured the rest of the steps

Thanks

Thanks

a) water level in A increase at 4cm/m, while that of B decrease by 2cm/m. (X*4) = (15 - X*2). Hence, time taken = X = 2.5 min. b) height at that point = 2.5*4 = 10cm

(15 - X*2) how u get 15

15 is the full height of tank B. As B is draining water out, so we deduct the X*2 from 15.

Tks

Why take take B height?

Hope this is clearer

Sorry. Should be H inside the tank as height, not X

I don't see any shaded parts in the qn ?

thats why

i dont understand

may be printing error

Clearly there is a mistake in the qn cos qn says "..... rectangle as shown below but there isn't any.

yahh

i go check it out

Good day to you, Ethan. Perhaps you are not aware that children come to this forum for help as well. Your profile picture might not be appropriate in that context. Sorry, I am not the ethics police of course, but we do need to be mindful of the youngsters. Thank you, Sir.

ok

Thank you

Find the LCM of 6 and 9.

Beside LCM 6 & 9. Is there other way to solve.

Unlikely

Can we use 60/6+9

Is this P4 question? Or P6?

P6

I also use LCM of 6,9

If one does not use the lowest common multiple of 6 and 9, the method frequently taught in school is listing. Red light flashed in minute: 0,6,12,18,....36,.....54,60 Yellow light flashed in minute : 0, 9, 18,.....36.....54 So by comparing one sees that the two lights flashed together at the start, the 18th, the 36th and the 54th minute. Hence four times in an hour, including the instance when Annette walked into the shop.