Add 12/42 and 21/90
12/42 + 21/90 is 109/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
12/42 = 12 × 15/42 × 15 = 180/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
180/630 + 147/630 = 180 + 147/630 = 327/630 - 327/630 simplified gives 109/210
- So, 12/42 + 21/90 = 109/210
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