Add 42/15 and 30/40
1st number: 2 12/15, 2nd number: 30/40
42/15 + 30/40 is 71/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
42/15 = 42 × 8/15 × 8 = 336/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
30/40 = 30 × 3/40 × 3 = 90/120 - Add the two like fractions:
336/120 + 90/120 = 336 + 90/120 = 426/120 - 426/120 simplified gives 71/20
- So, 42/15 + 30/40 = 71/20
In mixed form: 311/20
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