Add 42/10 and 21/84
1st number: 4 2/10, 2nd number: 21/84
42/10 + 21/84 is 89/20.
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,
42/10 = 42 × 42/10 × 42 = 1764/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Add the two like fractions:
1764/420 + 105/420 = 1764 + 105/420 = 1869/420 - 1869/420 simplified gives 89/20
- So, 42/10 + 21/84 = 89/20
In mixed form: 49/20
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