Add 3/8 and 7/21
3/8 + 7/21 is 17/24.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
3/8 = 3 × 21/8 × 21 = 63/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
7/21 = 7 × 8/21 × 8 = 56/168 - Add the two like fractions:
63/168 + 56/168 = 63 + 56/168 = 119/168 - 119/168 simplified gives 17/24
- So, 3/8 + 7/21 = 17/24
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