Add 21/98 and 72/90
21/98 + 72/90 is 71/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 98 and 90 is 4410
Next, find the equivalent fraction of both fractional numbers with denominator 4410 - For the 1st fraction, since 98 × 45 = 4410,
21/98 = 21 × 45/98 × 45 = 945/4410 - Likewise, for the 2nd fraction, since 90 × 49 = 4410,
72/90 = 72 × 49/90 × 49 = 3528/4410 - Add the two like fractions:
945/4410 + 3528/4410 = 945 + 3528/4410 = 4473/4410 - 4473/4410 simplified gives 71/70
- So, 21/98 + 72/90 = 71/70
In mixed form: 11/70
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