Add 3/42 and 21/90
3/42 + 21/90 is 32/105.
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,
3/42 = 3 × 15/42 × 15 = 45/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
45/630 + 147/630 = 45 + 147/630 = 192/630 - 192/630 simplified gives 32/105
- So, 3/42 + 21/90 = 32/105
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