As your math tutor, I’m here to help you break down factor pairs of 640 step by step!
Factor pairs of 640 are any two numbers that, when multiplied together, equal 640. The question to ask is “what two numbers multiplied together equal 640?” Every factor can be paired with another factor, and multiplying the two will result in 640.
To find the factor pairs of 640, follow these steps:
Step 1:
Find the smallest prime number that is larger than 1, and is a factor of 640. For reference, the first prime numbers to check are 2, 3, 5, 7, 11, and 13. In this case, the smallest factor that’s a prime number larger than 1 is 2.
Step 2:
Divide 640 by the smallest prime factor, in this case, 2:
640 ÷ 2 = 320
2 and 320 will make a new factor pair.
Step 3:
Repeat Steps 1 and 2, using 320 as the new focus. Find the smallest prime factor that isn’t 1, and divide 320 by that number. In this case, 2 is the new smallest prime factor:
320 ÷ 2 = 160
Remember that this new factor pair is only for the factors of 320, not 640. So, to finish the factor pair for 640, you’d multiply 2 and 2 before pairing with 160:
2 x 2 = 4
Step 4:
Repeat this process until there are no longer any prime factors larger than one to divide by. At the end, you should have the full list of factor pairs.
Here are all the factor pairs for 640:
(1, 640), (2, 320), (4, 160), (5, 128), (8, 80), (10, 64), (16, 40), (20, 32)
So, to list all the factors of 640: 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 320, 640
The negative factors of 640 would be: -1, -2, -4, -5, -8, -10, -16, -20, -32, -40, -64, -80, -128, -160, -320, -640
Now you’ve got it! A math tutor would always encourage you to practice with different numbers to reinforce your understanding of factor pairs. Try another one!