Add 21/90 and 7/80
21/90 + 7/80 is 77/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
7/80 = 7 × 9/80 × 9 = 63/720 - Add the two like fractions:
168/720 + 63/720 = 168 + 63/720 = 231/720 - 231/720 simplified gives 77/240
- So, 21/90 + 7/80 = 77/240
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