Add 30/42 and 21/30
30/42 + 21/30 is 99/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Add the two like fractions:
150/210 + 147/210 = 150 + 147/210 = 297/210 - 297/210 simplified gives 99/70
- So, 30/42 + 21/30 = 99/70
In mixed form: 129/70
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