Add 21/40 and 36/70
21/40 + 36/70 is 291/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
36/70 = 36 × 4/70 × 4 = 144/280 - Add the two like fractions:
147/280 + 144/280 = 147 + 144/280 = 291/280 - So, 21/40 + 36/70 = 291/280
In mixed form: 111/280
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