Add 21/45 and 18/40
21/45 + 18/40 is 11/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
18/40 = 18 × 9/40 × 9 = 162/360 - Add the two like fractions:
168/360 + 162/360 = 168 + 162/360 = 330/360 - 330/360 simplified gives 11/12
- So, 21/45 + 18/40 = 11/12
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