Seven people decide to share 3/8 of a bag of marbles equally. what fraction of the bag of marble does each person receive?

3/56 is the fraction of the bag of marble that each person receive.

bag of marbles = 3/8
divided by = 7 people

3/8 ÷ 7 

In dividing fraction, get the reciprocal of the 2nd fraction and multiply it to the 1st fraction.
1st fraction = 3/8
2nd fraction = 7 ⇒ 7/1 , reciprocal = 1/7

3/8 * 1/7 = 3 * 1 / 8 * 7 = 3/56  

each person will receive 3/56 of the bag of marbles.