Add 21/84 and 45/80
21/84 + 45/80 is 13/16.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
21/84 = 21 × 20/84 × 20 = 420/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
45/80 = 45 × 21/80 × 21 = 945/1680 - Add the two like fractions:
420/1680 + 945/1680 = 420 + 945/1680 = 1365/1680 - 1365/1680 simplified gives 13/16
- So, 21/84 + 45/80 = 13/16
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