Add 15/40 and 20/81
15/40 + 20/81 is 403/648.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 81 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 40 × 81 = 3240,
15/40 = 15 × 81/40 × 81 = 1215/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
20/81 = 20 × 40/81 × 40 = 800/3240 - Add the two like fractions:
1215/3240 + 800/3240 = 1215 + 800/3240 = 2015/3240 - 2015/3240 simplified gives 403/648
- So, 15/40 + 20/81 = 403/648
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