What exactly do you need help with??
Answer:
Step-by-step explanation:
Let the number = x.
We are trying to find out what number (x) we would need to add to 7/12 to get 4/15

Subtract 7/12 from both sides.
We need to make the denominators of the fractions the same.


So,

Answer:
3/20 is the answer.......

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