Help me break down this problem please!
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Question

Help me break down this problem please! 
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jravenv · Answer

attachment

zepdrix · Answer

$$\Large\rm \frac{a+2}{4b}-\frac{a-1}{10b}+\frac{a+3}{5b}$$

zepdrix · Answer

Ok I guess we want to start by finding the `Least Common Multiple` of the denominators :)

zepdrix · Answer

They all have a single b,
so b will be part of our multiple.

What else?
What's the least common multiple of 4, 5 and 10?

jravenv · Answer

20

zepdrix · Answer

Good good good :)
So each fraction needs a bottom of 20b.

zepdrix · Answer

$$\Large\rm \color{royalblue}{\frac{5}{5}}\left(\frac{a+2}{4b}\right)-\color{royalblue}{\frac{2}{2}}\left(\frac{a-1}{10b}\right)+\color{royalblue}{\frac{4}{4}}\left(\frac{a+3}{5b}\right)$$Do you see how this step will help us achieve that?

jravenv · Answer

I honestly don't sorry