Add 21/90 and 12/28
21/90 + 12/28 is 139/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 28 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 90 × 14 = 1260,
21/90 = 21 × 14/90 × 14 = 294/1260 - Likewise, for the 2nd fraction, since 28 × 45 = 1260,
12/28 = 12 × 45/28 × 45 = 540/1260 - Add the two like fractions:
294/1260 + 540/1260 = 294 + 540/1260 = 834/1260 - 834/1260 simplified gives 139/210
- So, 21/90 + 12/28 = 139/210
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