Add 21/70 and 28/20
1st number: 21/70, 2nd number: 1 8/20
21/70 + 28/20 is 17/10.
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,
28/20 = 28 × 7/20 × 7 = 196/140 - Add the two like fractions:
42/140 + 196/140 = 42 + 196/140 = 238/140 - 238/140 simplified gives 17/10
- So, 21/70 + 28/20 = 17/10
In mixed form: 17/10
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