Add 15/90 and 21/42
15/90 + 21/42 is 2/3.
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,
15/90 = 15 × 7/90 × 7 = 105/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630 - Add the two like fractions:
105/630 + 315/630 = 105 + 315/630 = 420/630 - 420/630 simplified gives 2/3
- So, 15/90 + 21/42 = 2/3
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