Add 21/36 and 81/70
1st number: 21/36, 2nd number: 1 11/70
21/36 + 81/70 is 731/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 70 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 36 × 35 = 1260,
21/36 = 21 × 35/36 × 35 = 735/1260 - Likewise, for the 2nd fraction, since 70 × 18 = 1260,
81/70 = 81 × 18/70 × 18 = 1458/1260 - Add the two like fractions:
735/1260 + 1458/1260 = 735 + 1458/1260 = 2193/1260 - 2193/1260 simplified gives 731/420
- So, 21/36 + 81/70 = 731/420
In mixed form: 1311/420
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