Dairon needs 20 pieces of string 3/8 inch in length. He cut a 4 7/8 inch piece of string into pieces that are 3/8 of an inch long each. How many more pieces of string does he need?

From the information given, Dairon already had a string that is 4 7/8 inches long.

We first write or simplify 3/8 and 4 7/8 in their decimal fraction forms.

3/8 is written as 0.375 and 4 7/8 is written as 4.875

We can now find out how many pieces he cut from the string (that was 4 7/8 inches), so:

4.875 : 0.375 = 13

So he got 13 pieces of string. He wants 20 pieces, so;

20 - 13 = 7

Therefore he will need 7 more strings.