Add 21/30 and 12/42
21/30 + 12/42 is 69/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 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 42 × 5 = 210,
12/42 = 12 × 5/42 × 5 = 60/210 - Add the two like fractions:
147/210 + 60/210 = 147 + 60/210 = 207/210 - 207/210 simplified gives 69/70
- So, 21/30 + 12/42 = 69/70
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