Add 90/5 and 7/21
1st number: 18 0/5, 2nd number: 7/21
90/5 + 7/21 is 55/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
90/5 = 90 × 21/5 × 21 = 1890/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Add the two like fractions:
1890/105 + 35/105 = 1890 + 35/105 = 1925/105 - 1925/105 simplified gives 55/3
- So, 90/5 + 7/21 = 55/3
In mixed form: 181/3
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