Add 40/90 and 21/80
40/90 + 21/80 is 509/720.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
40/90 = 40 × 8/90 × 8 = 320/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Add the two like fractions:
320/720 + 189/720 = 320 + 189/720 = 509/720 - So, 40/90 + 21/80 = 509/720
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