Add 72/90 and 75/80
72/90 + 75/80 is 139/80.
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,
72/90 = 72 × 8/90 × 8 = 576/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
75/80 = 75 × 9/80 × 9 = 675/720 - Add the two like fractions:
576/720 + 675/720 = 576 + 675/720 = 1251/720 - 1251/720 simplified gives 139/80
- So, 72/90 + 75/80 = 139/80
In mixed form: 159/80
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