Add 40/90 and 21/63
40/90 + 21/63 is 7/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 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 63 × 10 = 630,
21/63 = 21 × 10/63 × 10 = 210/630 - Add the two like fractions:
280/630 + 210/630 = 280 + 210/630 = 490/630 - 490/630 simplified gives 7/9
- So, 40/90 + 21/63 = 7/9
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