Add 21/40 and 18/90
21/40 + 18/90 is 29/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 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 90 × 4 = 360,
18/90 = 18 × 4/90 × 4 = 72/360 - Add the two like fractions:
189/360 + 72/360 = 189 + 72/360 = 261/360 - 261/360 simplified gives 29/40
- So, 21/40 + 18/90 = 29/40
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