Add 21/40 and 45/75
21/40 + 45/75 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 75 is 600
Next, find the equivalent fraction of both fractional numbers with denominator 600 - For the 1st fraction, since 40 × 15 = 600,
21/40 = 21 × 15/40 × 15 = 315/600 - Likewise, for the 2nd fraction, since 75 × 8 = 600,
45/75 = 45 × 8/75 × 8 = 360/600 - Add the two like fractions:
315/600 + 360/600 = 315 + 360/600 = 675/600 - 675/600 simplified gives 9/8
- So, 21/40 + 45/75 = 9/8
In mixed form: 11/8
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