Add 21/36 and 42/70
21/36 + 42/70 is 71/60.
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,
42/70 = 42 × 18/70 × 18 = 756/1260 - Add the two like fractions:
735/1260 + 756/1260 = 735 + 756/1260 = 1491/1260 - 1491/1260 simplified gives 71/60
- So, 21/36 + 42/70 = 71/60
In mixed form: 111/60
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