Help me please i don't know what i'm doing please help -9
9

-1/9

Step by step explanation:

The common difference of an arithmetic sequence can be found by picking 2 consecutive terms, and subtracting the second from the first. For example, if I chose the terms 2 and 1 8/9, I would find the common difference by:

1 8/9 - 2, which is equal to -1/9.

You can confirm this by picking another pair of consecutive terms. Let's pick 1 7/9 and 1 2/3:

1 2/3 - 1 7/9 = -1/9, as 1 2/3 = 1 6/9, so 1 6/9 - 1 7/9 = -1/9

the 8 in 8,420 is in the thousands place so it's value is 8 thousand.

the 8 in 6,870 is in the hundreds place so it's value is 8 hundred.

divide 8000 by 800 to find the answer:

8000 / 800 = 10

the 8 in 8,420 is 10 times greater than the 8 in 6,870