Add 42/70 and 30/40
42/70 + 30/40 is 27/20.
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,
42/70 = 42 × 4/70 × 4 = 168/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
30/40 = 30 × 7/40 × 7 = 210/280 - Add the two like fractions:
168/280 + 210/280 = 168 + 210/280 = 378/280 - 378/280 simplified gives 27/20
- So, 42/70 + 30/40 = 27/20
In mixed form: 17/20
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