Add 21/40 and 21/70
21/40 + 21/70 is 33/40.
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,
21/70 = 21 × 4/70 × 4 = 84/280 - Add the two like fractions:
147/280 + 84/280 = 147 + 84/280 = 231/280 - 231/280 simplified gives 33/40
- So, 21/40 + 21/70 = 33/40
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