You must find out when those days will occur at the same time.
Simplest answer is 7 x 30 = 210 days
If you count by 30 you get : 30, 60,90,120,150,180,210 and you see that no number is divisible by 7 until you reach 210 so this is for sure the answer.
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Answer:
A full moon occurs every 30 days
A Friday occurs every 7 days
You must find out when those days will occur at the same time.
Simplest answer is 7 x 30 = 210 days
If you count by 30 you get : 30, 60,90,120,150,180,210 and you see that no number is divisible by 7 until you reach 210 so this is for sure the answer.