Add 7/81 and 42/40
1st number: 7/81, 2nd number: 1 2/40
7/81 + 42/40 is 1841/1620.
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,
7/81 = 7 × 40/81 × 40 = 280/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
42/40 = 42 × 81/40 × 81 = 3402/3240 - Add the two like fractions:
280/3240 + 3402/3240 = 280 + 3402/3240 = 3682/3240 - 3682/3240 simplified gives 1841/1620
- So, 7/81 + 42/40 = 1841/1620
In mixed form: 1221/1620
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