# math

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I need to find the sum of 2/5 and 3/4. The LCD is 20 so I did 2x4=8 and 3x5=15. so I got 8/20 + 15/20 = 23/20, but this does not match any of the answers I have to pick from. What am I doing wrong?

• math -

2/5 + 3/4 = 8/20 + 15/20 = 23/20 = 1.15

you are correct. answer key is bogus

• math -

or, 1 3/20

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