Add 12/70 and 42/90
12/70 + 42/90 is 67/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
12/70 = 12 × 9/70 × 9 = 108/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Add the two like fractions:
108/630 + 294/630 = 108 + 294/630 = 402/630 - 402/630 simplified gives 67/105
- So, 12/70 + 42/90 = 67/105
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