What is the fact family of 28 and 1?

Answer 1

Factoring means to break a number down to it's basic parts, or "factors". The basic parts of X are numbers that are multiplied together to get X.

Take the number 28. Well it's even, so we know we can divide by '2'.

28/2 = 14 same as 2 x 14 = 28; so 2 and 14 are factors of 28. But we have more to do. 14 can be divided again, this time 2 x 7. So now we have, as factors of 28,

{2, 2, 7}. What we mean is, 2 x 2 x 7 = 28. Can we go any further?

No, because the only factors of 2 are {2, 1}, and for 7, {7, 1}. A number is called 'prime' when it's only factors are {itself, and 1}. In 'factoring' we are finished when all the terms are prime numbers. Easy prime numbers: {1,2,3,5,7,11,13,17,19,23.....} See if you can continue the list up to 100!