Add 21/40 and 3/45
21/40 + 3/45 is 71/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
3/45 = 3 × 8/45 × 8 = 24/360 - Add the two like fractions:
189/360 + 24/360 = 189 + 24/360 = 213/360 - 213/360 simplified gives 71/120
- So, 21/40 + 3/45 = 71/120
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