Add 9/80 and 21/81
9/80 + 21/81 is 803/2160.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 81 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 80 × 81 = 6480,
9/80 = 9 × 81/80 × 81 = 729/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
21/81 = 21 × 80/81 × 80 = 1680/6480 - Add the two like fractions:
729/6480 + 1680/6480 = 729 + 1680/6480 = 2409/6480 - 2409/6480 simplified gives 803/2160
- So, 9/80 + 21/81 = 803/2160
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