Add 21/10 and 42/84
1st number: 2 1/10, 2nd number: 42/84
21/10 + 42/84 is 13/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 10 × 42 = 420,
21/10 = 21 × 42/10 × 42 = 882/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Add the two like fractions:
882/420 + 210/420 = 882 + 210/420 = 1092/420 - 1092/420 simplified gives 13/5
- So, 21/10 + 42/84 = 13/5
In mixed form: 23/5
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