The square is divided into 3 parts.
part a is 1/3 of the area of the square.
part b is 2/5 of the area of the square.
what fraction of the area of the square is part c?
show your method.

1/3= 5/15
2/5= 6/15

5/15 + 6/15 = 11/15

15/15 - 11/15 = 4/15

Part C= 4/15

The total whole number area of the square = 1.

Part A + Part B + Part C = 1.

1/3  +  2/5 + C  = 1.

(5+ 6)/15 +    C  = 1.    LCM of 3 and 5 is 15.

11/15 + C = 1.

C =  1/1 - 11/15   = (15 -11)/15

C = 4/15.

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