Add 7/40 and 15/81
7/40 + 15/81 is 389/1080.
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,
7/40 = 7 × 81/40 × 81 = 567/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
15/81 = 15 × 40/81 × 40 = 600/3240 - Add the two like fractions:
567/3240 + 600/3240 = 567 + 600/3240 = 1167/3240 - 1167/3240 simplified gives 389/1080
- So, 7/40 + 15/81 = 389/1080
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