As your math tutor, I’m here to help you break down factor pairs of 400 step by step!
Factor pairs of 400 are any two numbers that, when multiplied together, equal 400. The question to ask is “what two numbers multiplied together equal 400?” Every factor can be paired with another factor, and multiplying the two will result in 400.
To find the factor pairs of 400, follow these steps:
Step 1:
Find the smallest prime number that is larger than 1, and is a factor of 400. 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 400 by the smallest prime factor, in this case, 2:
400 ÷ 2 = 200
2 and 200 will make a new factor pair.
Step 3:
Repeat Steps 1 and 2, using 200 as the new focus. Find the smallest prime factor that isn’t 1, and divide 200 by that number. In this case, 2 is the new smallest prime factor:
200 ÷ 2 = 100
Remember that this new factor pair is only for the factors of 200, not 400. So, to finish the factor pair for 400, you’d multiply 2 and 2 before pairing with 100:
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 400:
(1, 400), (2, 200), (4, 100), (5, 80), (8, 50), (10, 40), (16, 25), (20, 20)
So, to list all the factors of 400: 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 200, 400
The negative factors of 400 would be: -1, -2, -4, -5, -8, -10, -16, -20, -25, -40, -50, -80, -100, -200, -400
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!