6000 + 500 + 7

6*1000 + 5*100 + 0*10 + 7*1

6*10

6*1000 + 5*100 + 0*10 + 7*1

6*10

^{3}+ 5*10^{2}+ 0*10^{1}+ 7*10^{0}(I especially like this exponential form because I believe it clearly shows how the position of the digits is related to place value. When you get into decimals, you will see that the exponents go -1, -2, -3, ... As you move to the right of the decimal point. These numbers are all base-10, but other number bases can be used, too. If this were a base-8 number, for example, its value would be 6*8^{3}+5*8^{2}+0*8^{1}+7*8^{0}.)