Add 42/15 and 21/40
1st number: 2 12/15, 2nd number: 21/40
42/15 + 21/40 is 133/40.
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,
21/40 = 21 × 3/40 × 3 = 63/120 - Add the two like fractions:
336/120 + 63/120 = 336 + 63/120 = 399/120 - 399/120 simplified gives 133/40
- So, 42/15 + 21/40 = 133/40
In mixed form: 313/40
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