Add 21/25 and 18/40
21/25 + 18/40 is 129/100.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 40 is 200
Next, find the equivalent fraction of both fractional numbers with denominator 200 - For the 1st fraction, since 25 × 8 = 200,
21/25 = 21 × 8/25 × 8 = 168/200 - Likewise, for the 2nd fraction, since 40 × 5 = 200,
18/40 = 18 × 5/40 × 5 = 90/200 - Add the two like fractions:
168/200 + 90/200 = 168 + 90/200 = 258/200 - 258/200 simplified gives 129/100
- So, 21/25 + 18/40 = 129/100
In mixed form: 129/100
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