Add 70/81 and 42/40
1st number: 70/81, 2nd number: 1 2/40
70/81 + 42/40 is 3101/1620.
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,
70/81 = 70 × 40/81 × 40 = 2800/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
42/40 = 42 × 81/40 × 81 = 3402/3240 - Add the two like fractions:
2800/3240 + 3402/3240 = 2800 + 3402/3240 = 6202/3240 - 6202/3240 simplified gives 3101/1620
- So, 70/81 + 42/40 = 3101/1620
In mixed form: 11481/1620
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