Add 42/35 and 21/20
1st number: 1 7/35, 2nd number: 1 1/20
42/35 + 21/20 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 35 × 4 = 140,
42/35 = 42 × 4/35 × 4 = 168/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Add the two like fractions:
168/140 + 147/140 = 168 + 147/140 = 315/140 - 315/140 simplified gives 9/4
- So, 42/35 + 21/20 = 9/4
In mixed form: 21/4
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