Add 12/21 and 45/70
12/21 + 45/70 is 17/14.
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,
12/21 = 12 × 10/21 × 10 = 120/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
45/70 = 45 × 3/70 × 3 = 135/210 - Add the two like fractions:
120/210 + 135/210 = 120 + 135/210 = 255/210 - 255/210 simplified gives 17/14
- So, 12/21 + 45/70 = 17/14
In mixed form: 13/14
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