Add 9/40 and 12/21
9/40 + 12/21 is 223/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
9/40 = 9 × 21/40 × 21 = 189/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
12/21 = 12 × 40/21 × 40 = 480/840 - Add the two like fractions:
189/840 + 480/840 = 189 + 480/840 = 669/840 - 669/840 simplified gives 223/280
- So, 9/40 + 12/21 = 223/280
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