Add 21/30 and 42/7
1st number: 21/30, 2nd number: 6 0/7
21/30 + 42/7 is 67/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 7 × 30 = 210,
42/7 = 42 × 30/7 × 30 = 1260/210 - Add the two like fractions:
147/210 + 1260/210 = 147 + 1260/210 = 1407/210 - 1407/210 simplified gives 67/10
- So, 21/30 + 42/7 = 67/10
In mixed form: 67/10
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