Add 72/21 and 90/5
1st number: 3 9/21, 2nd number: 18 0/5
72/21 + 90/5 is 150/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
72/21 = 72 × 5/21 × 5 = 360/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
90/5 = 90 × 21/5 × 21 = 1890/105 - Add the two like fractions:
360/105 + 1890/105 = 360 + 1890/105 = 2250/105 - 2250/105 simplified gives 150/7
- So, 72/21 + 90/5 = 150/7
In mixed form: 213/7
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