math, algebra
posted by Jasmine20 .
How is 28 a perfect number? Can someone explain this to me.
all i understand that all perfect numbers end in 6 and 8. But how and why is 28 a perfect number.
dimes are packaged 50 in a roll. quarters come 40 in a roll.susan b anthony dollars come in rolls of 25. how many rolls of each do you need to have an equal number of each coin
fulij
your answer has nothing to do towards what i'm asking
fulij please use the Post a New Question choice at the top of the page
28 is a perfect number because its proper divisors are 1, 2, 4, 7, and 14.
So 1 + 2 + 4 + 7 + 14 = 28.
Oh, and for a number to be a perfect number, it's proper divisors must add up to the original number. Just like I showed you about with 28. Another example is the number six. It's proper divisors are 1, 2, and 3. So 1 + 2 + 3 = 6.
Thank you I will study of from what you explained to me.
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