Add 15/20 and 21/70
15/20 + 21/70 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
15/20 = 15 × 7/20 × 7 = 105/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Add the two like fractions:
105/140 + 42/140 = 105 + 42/140 = 147/140 - 147/140 simplified gives 21/20
- So, 15/20 + 21/70 = 21/20
In mixed form: 11/20
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