The digit 5 appears twice in the number 255,120. How does the total value of the 5 on the right compare to the total value of the 5 on the left?

The value of the first "" in the number is ten times that of the second "" in this number.

Step-by-step explanation:

What gives the number "" its value? Of course, each of its six digits has contributed. However, their significance are not exactly the same. For example, changing the first to would give and increase the value of this number by . On the other hand, changing the second to would give , which is an increase of only compared to the original number.

The order of these two digits matter because the number "" is written using positional notation. In this notation, the position of each digits gives the digit a unique weight. For example, in :

.

(Note that the index starts at from the right-hand side.)

Using these weights, the value can be written as the sum:

.

As seen in this sum, the first "" contributed to the total value, while the second "" contributed only .

Hence: The value of the first "" in the number is ten times that of the second "" in this number.  

12cm

the answer is d