Add 21/81 and 28/40
21/81 + 28/40 is 259/270.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 40 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 81 × 40 = 3240,
21/81 = 21 × 40/81 × 40 = 840/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
28/40 = 28 × 81/40 × 81 = 2268/3240 - Add the two like fractions:
840/3240 + 2268/3240 = 840 + 2268/3240 = 3108/3240 - 3108/3240 simplified gives 259/270
- So, 21/81 + 28/40 = 259/270
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