MHB Fraction Multiplication: How to Multiply Fractions and Mixed Numbers

AI Thread Summary
To solve the problem of how many boxes of paper remain after giving away half of 3 1/4 boxes, the correct approach involves multiplying by 1/2. The calculation shows that half of 3 1/4 is 1 5/8 boxes. The confusion arises from misunderstanding the multiplication process and the conversion of mixed numbers to improper fractions. The solution can be visualized by breaking down the multiplication into simpler components, confirming that the answer is indeed 1 5/8. Understanding these steps clarifies the process of fraction multiplication and subtraction in this context.
David39ni
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I am finding it hard to understand this questions its sounds more like fraction subtraction than multiple but the army test sample questions says its multipication

You have 3 1/4 boxes of paper. You give 1/2 to the paper to a colleague, how many boxes of paper do you have left.

The test says 1 5/8 i don't understand how they get to that. Now when i did prob did it wrong i got 22 / 12 I don't now how they get 1 5/8.

This is not home work this is revision questions available on the site to practise the type of quesitons I might be getting.
 
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Hello and welcome to MHB, David39ni! (Wave)

If you give away 1/2, then you have 1/2 left. So all we need to do is find what one-half of what you began with is:

$$\frac{1}{2}\cdot3\tfrac{1}{4}=\frac{1}{2}\cdot\frac{3\cdot4+1}{4}=\frac{1}{2}\cdot\frac{13}{4}=\frac{13}{8}=\frac{8+5}{8}=1\tfrac{5}{8}$$

Does that make sense?
 
Not really sorry wish this site had videos you still don't how their answer what i said ?
 
David39ni said:
Not really sorry wish this site had videos you still don't how their answer what i said ?

I am assuming you understand that if you give half of something away, you are left with one-half yourself.

Another way to look at finding one half of the original amount is:

$$\frac{1}{2}\cdot3\tfrac{1}{4}=\frac{1}{2}\left(3+\frac{1}{4}\right)=1\tfrac{1}{2}+\frac{1}{8}=1\tfrac{4}{8}+\frac{1}{8}=1\tfrac{5}{8}$$

This is actually more in line with how I would picture it mentally. :D
 
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