Add 8/21 and 45/70
8/21 + 45/70 is 43/42.
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,
8/21 = 8 × 10/21 × 10 = 80/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
45/70 = 45 × 3/70 × 3 = 135/210 - Add the two like fractions:
80/210 + 135/210 = 80 + 135/210 = 215/210 - 215/210 simplified gives 43/42
- So, 8/21 + 45/70 = 43/42
In mixed form: 11/42
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