Add 21/18 and 42/40
1st number: 1 3/18, 2nd number: 1 2/40
21/18 + 42/40 is 133/60.
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,
21/18 = 21 × 20/18 × 20 = 420/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Add the two like fractions:
420/360 + 378/360 = 420 + 378/360 = 798/360 - 798/360 simplified gives 133/60
- So, 21/18 + 42/40 = 133/60
In mixed form: 213/60
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