Add 20/15 and 90/70
1st number: 1 5/15, 2nd number: 1 20/70
20/15 + 90/70 is 55/21.
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,
20/15 = 20 × 14/15 × 14 = 280/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Add the two like fractions:
280/210 + 270/210 = 280 + 270/210 = 550/210 - 550/210 simplified gives 55/21
- So, 20/15 + 90/70 = 55/21
In mixed form: 213/21
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