Answer: A) 15/70
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Step-by-step explanation:
We multiply the numbers across the top (numerator) to get 3*5 = 15
Then across the bottom (denominator), we multiply the values to get 10*7 = 70
So we get
That's how we end up with 15/70
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Extra info:
Note how 15 and 70 have the GCF 5, so we can divide both values by 5
This means 15/70 reduces to 3/14; however, your teacher has decided not to reduce (since 3/14 is not one of the answers). So that means we should stick with 15/70 instead.