Add 40/70 and 30/90
40/70 + 30/90 is 19/21.
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,
40/70 = 40 × 9/70 × 9 = 360/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
30/90 = 30 × 7/90 × 7 = 210/630 - Add the two like fractions:
360/630 + 210/630 = 360 + 210/630 = 570/630 - 570/630 simplified gives 19/21
- So, 40/70 + 30/90 = 19/21
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