Add 21/72 and 18/70
21/72 + 18/70 is 461/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 70 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 72 × 35 = 2520,
21/72 = 21 × 35/72 × 35 = 735/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
18/70 = 18 × 36/70 × 36 = 648/2520 - Add the two like fractions:
735/2520 + 648/2520 = 735 + 648/2520 = 1383/2520 - 1383/2520 simplified gives 461/840
- So, 21/72 + 18/70 = 461/840
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