Add 30/90 and 40/42
30/90 + 40/42 is 9/7.
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,
30/90 = 30 × 7/90 × 7 = 210/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
40/42 = 40 × 15/42 × 15 = 600/630 - Add the two like fractions:
210/630 + 600/630 = 210 + 600/630 = 810/630 - 810/630 simplified gives 9/7
- So, 30/90 + 40/42 = 9/7
In mixed form: 12/7
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