Add 21/90 and 21/40
21/90 + 21/40 is 91/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
84/360 + 189/360 = 84 + 189/360 = 273/360 - 273/360 simplified gives 91/120
- So, 21/90 + 21/40 = 91/120
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