## Secondary 4 eMaths question

PSLE marks the graduation of Primary school students and their entry into Secondary schools as teenagers. Discuss all issues about Secondary schooling here.

### Secondary 4 eMaths question

hi,
Can someone help to solve this question

Mr Lai take X mins to carve a block of ice to swan, Mr Han takes 25 mins more to carve the same size of ice block to swan. if they carve the block of ice together only take 30 Mins to complete. derive all the above to the following equation
X^2-35X-750 = 0

bluesky63
YellowBelt

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### Re: Secondary 4 eMaths question

In 1 mins, Mr Lai can carve 1/X block and Mr Han can carve 1/(X+25) block
When they are working together,
In 1mins they can carve a total of 1/X+1/(X+25) block, and when this value is mutiplied by 30(mins), it will be equal to 1 block.

30[1/X+1/(X+25)]=1, mutiply both sides by X(X+25), re-arrange, we show the result.

FrekiWang
GreenBelt

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### Re: Secondary 4 eMaths question

Oh yes, thank you very much.

bluesky63
YellowBelt

Posts: 18
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