Answer:
a) the common difference is 20
b) 
c) the common difference is -13
d) 
Step-by-step explanation:
a) what is the common difference of the sequence xn
Looking at the table, we get x_3=16, x_4=36 and x_5= 56
Deterring the common difference by subtracting x_4 from x_3 we get
36-16 =20
So, the common difference is 20
b) what is x_8? what is x_12
The formula used is: 
We know common difference d= 20, we need to find 
Using
we can find 

So, We have 
Now finding 

So, 
Now finding 

So, 
c) what is the common difference of the sequence 
Looking at the table, we get a_7=104, a_8=91 and a_9= 78
Deterring the common difference by subtracting a_7 from a_8 we get
91-104 =-13
So, the common difference is -13
d) what is a_12? what is a_15?
The formula used is: 
We know common difference d= -13, we need to find 
Using
we can find 

So, We have 
Now finding
, put n=12

So, 
Now finding
, put n=15

So, 
Answer:
0.24 > 0.18
Step-by-step explanation:
Given that,
Bob's stack = 0.2m
Cal's stack = 0.24m
Pete's stack = 0.18m
To find?
A number sentence.
<em>A simple sentence is a string/collection of words that contain a subject and a verb whereas a number sentence is a sentence that consist of </em><em>mathematical operation</em><em> like +, -, /, * together with an equality such as =, <, >, and like a sentence it also tell a fact.</em>
<em> </em>So, the number sentence that compares cal's stack of cards to Pete's stack is
<h2>0.24 > 0.18</h2>
<em />
<em />
<em> </em>
Here, I am not sure, try this.