Add 21/40 and 10/18
21/40 + 10/18 is 389/360.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
10/18 = 10 × 20/18 × 20 = 200/360 - Add the two like fractions:
189/360 + 200/360 = 189 + 200/360 = 389/360 - So, 21/40 + 10/18 = 389/360
In mixed form: 129/360
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