Add 30/70 and 70/21
1st number: 30/70, 2nd number: 3 7/21
30/70 + 70/21 is 79/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
30/70 = 30 × 3/70 × 3 = 90/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
70/21 = 70 × 10/21 × 10 = 700/210 - Add the two like fractions:
90/210 + 700/210 = 90 + 700/210 = 790/210 - 790/210 simplified gives 79/21
- So, 30/70 + 70/21 = 79/21
In mixed form: 316/21
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