Add 28/21 and 45/70
1st number: 1 7/21, 2nd number: 45/70
28/21 + 45/70 is 83/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
45/70 = 45 × 3/70 × 3 = 135/210 - Add the two like fractions:
280/210 + 135/210 = 280 + 135/210 = 415/210 - 415/210 simplified gives 83/42
- So, 28/21 + 45/70 = 83/42
In mixed form: 141/42
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