Add 15/42 and 40/80
15/42 + 40/80 is 6/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
15/42 = 15 × 40/42 × 40 = 600/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
40/80 = 40 × 21/80 × 21 = 840/1680 - Add the two like fractions:
600/1680 + 840/1680 = 600 + 840/1680 = 1440/1680 - 1440/1680 simplified gives 6/7
- So, 15/42 + 40/80 = 6/7
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