First, we make the denominators of 1/4 and 3/8 the same as the LCM (= 8)-> 1/4 = 1 x 2 / 4 x 2 = 2/8-> 1 - ... = 2/8 + 3/8 = 5/8The missing fraction = 1 - 5/8 = 3/8.
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