Add 40/42 and 15/45
40/42 + 15/45 is 9/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
40/42 = 40 × 15/42 × 15 = 600/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
15/45 = 15 × 14/45 × 14 = 210/630 - Add the two like fractions:
600/630 + 210/630 = 600 + 210/630 = 810/630 - 810/630 simplified gives 9/7
- So, 40/42 + 15/45 = 9/7
In mixed form: 12/7
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