Add 21/70 and 7/20
21/70 + 7/20 is 13/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
7/20 = 7 × 7/20 × 7 = 49/140 - Add the two like fractions:
42/140 + 49/140 = 42 + 49/140 = 91/140 - 91/140 simplified gives 13/20
- So, 21/70 + 7/20 = 13/20
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