Add 45/15 and 21/84
1st number: 3 0/15, 2nd number: 21/84
45/15 + 21/84 is 13/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 15 × 28 = 420,
45/15 = 45 × 28/15 × 28 = 1260/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Add the two like fractions:
1260/420 + 105/420 = 1260 + 105/420 = 1365/420 - 1365/420 simplified gives 13/4
- So, 45/15 + 21/84 = 13/4
In mixed form: 31/4
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