Add 7/20 and 21/40
7/20 + 21/40 is 7/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
7/20 = 7 × 2/20 × 2 = 14/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Add the two like fractions:
14/40 + 21/40 = 14 + 21/40 = 35/40 - 35/40 simplified gives 7/8
- So, 7/20 + 21/40 = 7/8
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