Add 21/35 and 42/81
21/35 + 42/81 is 151/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 81 is 2835
Next, find the equivalent fraction of both fractional numbers with denominator 2835 - For the 1st fraction, since 35 × 81 = 2835,
21/35 = 21 × 81/35 × 81 = 1701/2835 - Likewise, for the 2nd fraction, since 81 × 35 = 2835,
42/81 = 42 × 35/81 × 35 = 1470/2835 - Add the two like fractions:
1701/2835 + 1470/2835 = 1701 + 1470/2835 = 3171/2835 - 3171/2835 simplified gives 151/135
- So, 21/35 + 42/81 = 151/135
In mixed form: 116/135
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