Add 18/40 and 21/72
18/40 + 21/72 is 89/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
18/40 = 18 × 9/40 × 9 = 162/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Add the two like fractions:
162/360 + 105/360 = 162 + 105/360 = 267/360 - 267/360 simplified gives 89/120
- So, 18/40 + 21/72 = 89/120
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