Add 21/36 and 18/40
21/36 + 18/40 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 36 × 10 = 360,
21/36 = 21 × 10/36 × 10 = 210/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
18/40 = 18 × 9/40 × 9 = 162/360 - Add the two like fractions:
210/360 + 162/360 = 210 + 162/360 = 372/360 - 372/360 simplified gives 31/30
- So, 21/36 + 18/40 = 31/30
In mixed form: 11/30
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