Add 21/70 and 30/40
21/70 + 30/40 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
30/40 = 30 × 7/40 × 7 = 210/280 - Add the two like fractions:
84/280 + 210/280 = 84 + 210/280 = 294/280 - 294/280 simplified gives 21/20
- So, 21/70 + 30/40 = 21/20
In mixed form: 11/20
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