Add 21/15 and 72/70
1st number: 1 6/15, 2nd number: 1 2/70
21/15 + 72/70 is 17/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
72/70 = 72 × 3/70 × 3 = 216/210 - Add the two like fractions:
294/210 + 216/210 = 294 + 216/210 = 510/210 - 510/210 simplified gives 17/7
- So, 21/15 + 72/70 = 17/7
In mixed form: 23/7
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