Add 12/80 and 70/81
12/80 + 70/81 is 1643/1620.
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,
12/80 = 12 × 81/80 × 81 = 972/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
70/81 = 70 × 80/81 × 80 = 5600/6480 - Add the two like fractions:
972/6480 + 5600/6480 = 972 + 5600/6480 = 6572/6480 - 6572/6480 simplified gives 1643/1620
- So, 12/80 + 70/81 = 1643/1620
In mixed form: 123/1620
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