Add 21/35 and 20/72
21/35 + 20/72 is 79/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 35 × 72 = 2520,
21/35 = 21 × 72/35 × 72 = 1512/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
20/72 = 20 × 35/72 × 35 = 700/2520 - Add the two like fractions:
1512/2520 + 700/2520 = 1512 + 700/2520 = 2212/2520 - 2212/2520 simplified gives 79/90
- So, 21/35 + 20/72 = 79/90
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