Add 72/70 and 28/21
1st number: 1 2/70, 2nd number: 1 7/21
72/70 + 28/21 is 248/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
72/70 = 72 × 3/70 × 3 = 216/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Add the two like fractions:
216/210 + 280/210 = 216 + 280/210 = 496/210 - 496/210 simplified gives 248/105
- So, 72/70 + 28/21 = 248/105
In mixed form: 238/105
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