Add 7/40 and 9/21
7/40 + 9/21 is 169/280.
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,
7/40 = 7 × 21/40 × 21 = 147/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
9/21 = 9 × 40/21 × 40 = 360/840 - Add the two like fractions:
147/840 + 360/840 = 147 + 360/840 = 507/840 - 507/840 simplified gives 169/280
- So, 7/40 + 9/21 = 169/280
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