Add 20/21 and 18/24
20/21 + 18/24 is 143/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 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 24 × 7 = 168,
18/24 = 18 × 7/24 × 7 = 126/168 - Add the two like fractions:
160/168 + 126/168 = 160 + 126/168 = 286/168 - 286/168 simplified gives 143/84
- So, 20/21 + 18/24 = 143/84
In mixed form: 159/84
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