Add 3/8 and 18/21
3/8 + 18/21 is 69/56.
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,
18/21 = 18 × 8/21 × 8 = 144/168 - Add the two like fractions:
63/168 + 144/168 = 63 + 144/168 = 207/168 - 207/168 simplified gives 69/56
- So, 3/8 + 18/21 = 69/56
In mixed form: 113/56
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