Add 21/35 and 15/40
21/35 + 15/40 is 39/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 35 × 8 = 280,
21/35 = 21 × 8/35 × 8 = 168/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
15/40 = 15 × 7/40 × 7 = 105/280 - Add the two like fractions:
168/280 + 105/280 = 168 + 105/280 = 273/280 - 273/280 simplified gives 39/40
- So, 21/35 + 15/40 = 39/40
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