Add 45/18 and 42/40
1st number: 2 9/18, 2nd number: 1 2/40
45/18 + 42/40 is 71/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
45/18 = 45 × 20/18 × 20 = 900/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Add the two like fractions:
900/360 + 378/360 = 900 + 378/360 = 1278/360 - 1278/360 simplified gives 71/20
- So, 45/18 + 42/40 = 71/20
In mixed form: 311/20
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