Add 21/63 and 40/70
21/63 + 40/70 is 19/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
21/63 = 21 × 10/63 × 10 = 210/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
40/70 = 40 × 9/70 × 9 = 360/630 - Add the two like fractions:
210/630 + 360/630 = 210 + 360/630 = 570/630 - 570/630 simplified gives 19/21
- So, 21/63 + 40/70 = 19/21
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