# 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

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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