Add 20/21 and 7/8
20/21 + 7/8 is 307/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
7/8 = 7 × 21/8 × 21 = 147/168 - Add the two like fractions:
160/168 + 147/168 = 160 + 147/168 = 307/168 - So, 20/21 + 7/8 = 307/168
In mixed form: 1139/168
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