Add 80/21 and 15/70
1st number: 3 17/21, 2nd number: 15/70
80/21 + 15/70 is 169/42.
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,
80/21 = 80 × 10/21 × 10 = 800/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
15/70 = 15 × 3/70 × 3 = 45/210 - Add the two like fractions:
800/210 + 45/210 = 800 + 45/210 = 845/210 - 845/210 simplified gives 169/42
- So, 80/21 + 15/70 = 169/42
In mixed form: 41/42
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