Add 21/90 and 42/45
21/90 + 42/45 is 7/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
42/45 = 42 × 2/45 × 2 = 84/90 - Add the two like fractions:
21/90 + 84/90 = 21 + 84/90 = 105/90 - 105/90 simplified gives 7/6
- So, 21/90 + 42/45 = 7/6
In mixed form: 11/6
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