Add 21/10 and 40/18
1st number: 2 1/10, 2nd number: 2 4/18
21/10 + 40/18 is 389/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 10 × 9 = 90,
21/10 = 21 × 9/10 × 9 = 189/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
40/18 = 40 × 5/18 × 5 = 200/90 - Add the two like fractions:
189/90 + 200/90 = 189 + 200/90 = 389/90 - So, 21/10 + 40/18 = 389/90
In mixed form: 429/90
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