Add 80/21 and 70/30
1st number: 3 17/21, 2nd number: 2 10/30
80/21 + 70/30 is 43/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 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 30 × 7 = 210,
70/30 = 70 × 7/30 × 7 = 490/210 - Add the two like fractions:
800/210 + 490/210 = 800 + 490/210 = 1290/210 - 1290/210 simplified gives 43/7
- So, 80/21 + 70/30 = 43/7
In mixed form: 61/7
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