Add 15/42 and 12/20
15/42 + 12/20 is 67/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
15/42 = 15 × 10/42 × 10 = 150/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420 - Add the two like fractions:
150/420 + 252/420 = 150 + 252/420 = 402/420 - 402/420 simplified gives 67/70
- So, 15/42 + 12/20 = 67/70
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