Add 21/90 and 21/42
21/90 + 21/42 is 11/15.
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,
21/42 = 21 × 15/42 × 15 = 315/630 - Add the two like fractions:
147/630 + 315/630 = 147 + 315/630 = 462/630 - 462/630 simplified gives 11/15
- So, 21/90 + 21/42 = 11/15
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