Add 42/90 and 54/21
1st number: 42/90, 2nd number: 2 12/21
42/90 + 54/21 is 319/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
54/21 = 54 × 30/21 × 30 = 1620/630 - Add the two like fractions:
294/630 + 1620/630 = 294 + 1620/630 = 1914/630 - 1914/630 simplified gives 319/105
- So, 42/90 + 54/21 = 319/105
In mixed form: 34/105
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