Add 30/90 and 21/80
30/90 + 21/80 is 143/240.
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,
30/90 = 30 × 8/90 × 8 = 240/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Add the two like fractions:
240/720 + 189/720 = 240 + 189/720 = 429/720 - 429/720 simplified gives 143/240
- So, 30/90 + 21/80 = 143/240
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