Add 21/84 and 45/40
1st number: 21/84, 2nd number: 1 5/40
21/84 + 45/40 is 11/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
21/84 = 21 × 10/84 × 10 = 210/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
45/40 = 45 × 21/40 × 21 = 945/840 - Add the two like fractions:
210/840 + 945/840 = 210 + 945/840 = 1155/840 - 1155/840 simplified gives 11/8
- So, 21/84 + 45/40 = 11/8
In mixed form: 13/8
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