Add 90/10 and 45/21
1st number: 9 0/10, 2nd number: 2 3/21
90/10 + 45/21 is 78/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
90/10 = 90 × 21/10 × 21 = 1890/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
45/21 = 45 × 10/21 × 10 = 450/210 - Add the two like fractions:
1890/210 + 450/210 = 1890 + 450/210 = 2340/210 - 2340/210 simplified gives 78/7
- So, 90/10 + 45/21 = 78/7
In mixed form: 111/7
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