Add 20/70 and 45/21
1st number: 20/70, 2nd number: 2 3/21
20/70 + 45/21 is 17/7.
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,
20/70 = 20 × 3/70 × 3 = 60/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
45/21 = 45 × 10/21 × 10 = 450/210 - Add the two like fractions:
60/210 + 450/210 = 60 + 450/210 = 510/210 - 510/210 simplified gives 17/7
- So, 20/70 + 45/21 = 17/7
In mixed form: 23/7
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