Add 21/18 and 7/40
1st number: 1 3/18, 2nd number: 7/40
21/18 + 7/40 is 161/120.
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,
7/40 = 7 × 9/40 × 9 = 63/360 - Add the two like fractions:
420/360 + 63/360 = 420 + 63/360 = 483/360 - 483/360 simplified gives 161/120
- So, 21/18 + 7/40 = 161/120
In mixed form: 141/120
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