Add 9/21 and 63/90
9/21 + 63/90 is 79/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
9/21 = 9 × 30/21 × 30 = 270/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
63/90 = 63 × 7/90 × 7 = 441/630 - Add the two like fractions:
270/630 + 441/630 = 270 + 441/630 = 711/630 - 711/630 simplified gives 79/70
- So, 9/21 + 63/90 = 79/70
In mixed form: 19/70
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