Add 90/70 and 15/21
1st number: 1 20/70, 2nd number: 15/21
90/70 + 15/21 is 2/1.
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,
90/70 = 90 × 3/70 × 3 = 270/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
15/21 = 15 × 10/21 × 10 = 150/210 - Add the two like fractions:
270/210 + 150/210 = 270 + 150/210 = 420/210 - 420/210 simplified gives 2/1
- So, 90/70 + 15/21 = 2/1
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