Question
A whole number is called a perfect number when the sum of its factors that are less than the number equals the number. For example, 6 is a perfect number, because $1+2+3=6 .$ Find the factors of $28 .$ Then use addition to show that 28 is also a perfect number.
Step 1
The factors of a number are the numbers that divide evenly into that number. For 28, the factors are $1, 2, 4, 7, 14, 28$. Show more…
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