So lets see how does knowing that 5 divided by 8 = 0.625 helps us write the decimal for 4 5/8. First lets write 5 divided by 8 like a fraction: 5/8=0.625. Now we can see that 5/8 is in the number 4 5/8 so we can easily write it as: 4 + 0.625 = 4.625. So this is how it helps us.