Add 21/90 and 54/42
1st number: 21/90, 2nd number: 1 12/42
21/90 + 54/42 is 319/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
54/42 = 54 × 15/42 × 15 = 810/630 - Add the two like fractions:
147/630 + 810/630 = 147 + 810/630 = 957/630 - 957/630 simplified gives 319/210
- So, 21/90 + 54/42 = 319/210
In mixed form: 1109/210
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