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Algebraic fractions

Can someone help me do this question please I'm stuck :frown:

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Original post by skyhigh12
Can someone help me do this question please I'm stuck :frown:

Posted from TSR Mobile


1. find a common denominator (this is the lowest common multiple of the fractions- so in this case 6)
2. multiply both sides through by that LCM (so you get 3x + 2x = 180)
3. simplify and solve for x (so 5x=180, therefore x=36)


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Reply 2
Thanks lot for your help :smile: so when you find the common denominator you have to multiply the fractions diagonally right? E.g 3 times X and 2 times X

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Original post by skyhigh12
Thanks lot for your help :smile: so when you find the common denominator you have to multiply the fractions diagonally right? E.g 3 times X and 2 times X

Posted from TSR Mobile


The absolute easiest way of doing these questions, is by multiplying everything by each denominator. So first times all 3 number by 2, then by 3. A common denominator is not needed for questions where you need to find X.
Reply 4
Could anyone help on this aswell?
I would really appreciate it
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Reply 5
Original post by fajitamunch
The absolute easiest way of doing these questions, is by multiplying everything by each denominator. So first times all 3 number by 2, then by 3. A common denominator is not needed for questions where you need to find X.


This is no different to the previous solution. What you're doing is the same thing because you're multiplying by 2; then by 3 which would be 2x3=6 and you're done much faster.

@skyhigh12: In problems like these what you need to do is get rid of the fractions. To do that you have to multiply by a common denominator as it was suggested earlier.

What's troubling you?
Reply 6
Thanks guys I get it now, could you lot help me on the last two questions I posted on my last comment please

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Reply 7
Original post by willius
This is no different to the previous solution. What you're doing is the same thing because you're multiplying by 2; then by 3 which would be 2x3=6 and you're done much faster.

@skyhigh12: In problems like these what you need to do is get rid of the fractions. To do that you have to multiply by a common denominator as it was suggested earlier.

What's troubling you?


Well it is different, because in more complex equations where you have denominators of like 43, 57, 54 etc, good luck finding a common denominator.
Reply 9
Original post by skyhigh12
Could anyone help on this aswell?
I would really appreciate it
Posted from TSR Mobile


For your second link, the 'm' stands for midpoint - the middle value. You can find it by adding the grouped data (20 < a < 30 => 20+30 = 50) and the divide it by 2 (= 25). Then for the second midpoint, it would be 30+50 = 80 and divide it by 2 (= 40).

For the mxf, it means the midpoint multiplied by the frequency. So you'd do your first midpoint (25) and times it by your first frequency (20) and get 500. Then for the second mxf, it would be 40 x 40 = 1600.
First multiply everything by two, then multiply everything by 3, you should get 5x = 180, x = 36

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