Add 15/42 and 8/40
15/42 + 8/40 is 39/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
15/42 = 15 × 20/42 × 20 = 300/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
8/40 = 8 × 21/40 × 21 = 168/840 - Add the two like fractions:
300/840 + 168/840 = 300 + 168/840 = 468/840 - 468/840 simplified gives 39/70
- So, 15/42 + 8/40 = 39/70
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