Add 18/15 and 42/40
1st number: 1 3/15, 2nd number: 1 2/40
18/15 + 42/40 is 9/4.
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,
18/15 = 18 × 8/15 × 8 = 144/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
42/40 = 42 × 3/40 × 3 = 126/120 - Add the two like fractions:
144/120 + 126/120 = 144 + 126/120 = 270/120 - 270/120 simplified gives 9/4
- So, 18/15 + 42/40 = 9/4
In mixed form: 21/4
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