Will mark brainliest  1) identify and explain the error 2)show correct work and solution 3)what strategy did you use for solving this problem?

US postal service delivered = 7.14 x 10^10 pieces of mail in December.

US postal service delivered = 3.21 x 10^10 pieces of mail in January.

We need to find the total number of mail delivered in both months.

In the shown work you setup problem correctly.

You are adding

7.14 x 10^10

3.21 x 10^10

10.35 x10^10

You got 10.35 x10^10 on adding.

Therefore, second step is correct too.

But in third step when you moved decimal one place on left you wrote 1.035 x 10^10.

geometric series converge the common ratio r has magnitude less than one.

which is equivalent to

for the example we need

|2-x| < 1

-1 < 2-x   and 2-x < 1

x < 3 and x > 1

we can write that

answer: 1 < x < 3

1a. common ratio r=250/25=10 > 1     diverges

1b.   r=50/100=1/2 converges

when these converge they converge to

where a is the first term.

answer: 200

1c. r=-1   so it's not the case that |r| < 1.     diverges

2a. x is the common ratio so we converge when |x|< 1

2b.   r=-10x / -2 = 5x.

we converge when

|5x| < 1

|x| < 1/5

2c.   r=3-2x

-1 < 3-2x and 3-2x < 1

-4 < -2x and 2 < 2x

x < 2 and 1 < x

1 < x < 2

2d. [/tex] r=-48x^3/12 = 4x^3[/tex]

|4x^3| < 1

|x^3| < \frac 1 4

|x| < 4^{-1/3}