Add 18/40 and 45/21
1st number: 18/40, 2nd number: 2 3/21
18/40 + 45/21 is 363/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
45/21 = 45 × 40/21 × 40 = 1800/840 - Add the two like fractions:
378/840 + 1800/840 = 378 + 1800/840 = 2178/840 - 2178/840 simplified gives 363/140
- So, 18/40 + 45/21 = 363/140
In mixed form: 283/140
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