Add 30/70 and 40/90
30/70 + 40/90 is 55/63.
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,
30/70 = 30 × 9/70 × 9 = 270/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
40/90 = 40 × 7/90 × 7 = 280/630 - Add the two like fractions:
270/630 + 280/630 = 270 + 280/630 = 550/630 - 550/630 simplified gives 55/63
- So, 30/70 + 40/90 = 55/63
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