Add 30/80 and 70/81
30/80 + 70/81 is 803/648.
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,
30/80 = 30 × 81/80 × 81 = 2430/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
70/81 = 70 × 80/81 × 80 = 5600/6480 - Add the two like fractions:
2430/6480 + 5600/6480 = 2430 + 5600/6480 = 8030/6480 - 8030/6480 simplified gives 803/648
- So, 30/80 + 70/81 = 803/648
In mixed form: 1155/648
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