Add 42/21 and 20/15
1st number: 2 0/21, 2nd number: 1 5/15
42/21 + 20/15 is 10/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
20/15 = 20 × 7/15 × 7 = 140/105 - Add the two like fractions:
210/105 + 140/105 = 210 + 140/105 = 350/105 - 350/105 simplified gives 10/3
- So, 42/21 + 20/15 = 10/3
In mixed form: 31/3
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