Add 21/5 and 20/7
1st number: 4 1/5, 2nd number: 2 6/7
21/5 + 20/7 is 247/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 7 is 35
Next, find the equivalent fraction of both fractional numbers with denominator 35 - For the 1st fraction, since 5 × 7 = 35,
21/5 = 21 × 7/5 × 7 = 147/35 - Likewise, for the 2nd fraction, since 7 × 5 = 35,
20/7 = 20 × 5/7 × 5 = 100/35 - Add the two like fractions:
147/35 + 100/35 = 147 + 100/35 = 247/35 - So, 21/5 + 20/7 = 247/35
In mixed form: 72/35
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