Add 3/40 and 9/21
3/40 + 9/21 is 141/280.
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,
3/40 = 3 × 21/40 × 21 = 63/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
9/21 = 9 × 40/21 × 40 = 360/840 - Add the two like fractions:
63/840 + 360/840 = 63 + 360/840 = 423/840 - 423/840 simplified gives 141/280
- So, 3/40 + 9/21 = 141/280
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