Add 9/21 and 7/40
9/21 + 7/40 is 169/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
9/21 = 9 × 40/21 × 40 = 360/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
7/40 = 7 × 21/40 × 21 = 147/840 - Add the two like fractions:
360/840 + 147/840 = 360 + 147/840 = 507/840 - 507/840 simplified gives 169/280
- So, 9/21 + 7/40 = 169/280
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