Add 30/80 and 80/90
30/80 + 80/90 is 91/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
30/80 = 30 × 9/80 × 9 = 270/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
80/90 = 80 × 8/90 × 8 = 640/720 - Add the two like fractions:
270/720 + 640/720 = 270 + 640/720 = 910/720 - 910/720 simplified gives 91/72
- So, 30/80 + 80/90 = 91/72
In mixed form: 119/72
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