Add 42/7 and 21/20
1st number: 6 0/7, 2nd number: 1 1/20
42/7 + 21/20 is 141/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
42/7 = 42 × 20/7 × 20 = 840/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Add the two like fractions:
840/140 + 147/140 = 840 + 147/140 = 987/140 - 987/140 simplified gives 141/20
- So, 42/7 + 21/20 = 141/20
In mixed form: 71/20
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