Add 40/90 and 42/21
1st number: 40/90, 2nd number: 2 0/21
40/90 + 42/21 is 22/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
40/90 = 40 × 7/90 × 7 = 280/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630 - Add the two like fractions:
280/630 + 1260/630 = 280 + 1260/630 = 1540/630 - 1540/630 simplified gives 22/9
- So, 40/90 + 42/21 = 22/9
In mixed form: 24/9
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