Add 70/30 and 72/21
1st number: 2 10/30, 2nd number: 3 9/21
70/30 + 72/21 is 121/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
70/30 = 70 × 7/30 × 7 = 490/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
72/21 = 72 × 10/21 × 10 = 720/210 - Add the two like fractions:
490/210 + 720/210 = 490 + 720/210 = 1210/210 - 1210/210 simplified gives 121/21
- So, 70/30 + 72/21 = 121/21
In mixed form: 516/21
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