Add 72/42 and 5/15
1st number: 1 30/42, 2nd number: 5/15
72/42 + 5/15 is 43/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
5/15 = 5 × 14/15 × 14 = 70/210 - Add the two like fractions:
360/210 + 70/210 = 360 + 70/210 = 430/210 - 430/210 simplified gives 43/21
- So, 72/42 + 5/15 = 43/21
In mixed form: 21/21
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