Add 21/72 and 42/40
1st number: 21/72, 2nd number: 1 2/40
21/72 + 42/40 is 161/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Add the two like fractions:
105/360 + 378/360 = 105 + 378/360 = 483/360 - 483/360 simplified gives 161/120
- So, 21/72 + 42/40 = 161/120
In mixed form: 141/120
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