Add 7/42 and 21/90
7/42 + 21/90 is 2/5.
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,
7/42 = 7 × 15/42 × 15 = 105/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
105/630 + 147/630 = 105 + 147/630 = 252/630 - 252/630 simplified gives 2/5
- So, 7/42 + 21/90 = 2/5
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