Given data :
a₃ = 9/16
aₓ = -3/4 · aₓ₋₁
Where x is the number of terms ('x' is also written as 'n')
To find the 7th term (a₇):
We know that aₓ = -3/4 · aₓ₋₁
So,
a₃ = -3/4 · a₃₋₁
a₃ = -3/4 · a₂
9/16 = -3/4 · a₂
a₂ = 9/16 × -4/3
a₂ = -36/48
a₂ = -3/4
Again,
aₓ = -3/4 · aₓ₋₁
a₄ = -3/4 · a₄₋₁
a₄ = -3/4 · a₃
a₄ = -3/4 · 9/16
a₄ = -27/64
a₄ = -27/64
For a₅,
aₓ = -3/4 · aₓ₋₁
a₅ = -3/4 · a₅₋₁
a₅ = -3/4 · a₄
a₅ = -3/4 × -27/64
a₅ = 81/256
For a₆,
aₓ = -3/4 · aₓ₋₁
a₆ = -3/4 · a₆₋₁
a₆ = -3/4 · a₅
a₆ = -3/4 × 81/256
a₆ = -243/1024
For a₇,
aₓ = -3/4 · aₓ₋₁
a₇ = -3/4 · a₇₋₁
a₇ = -3/4 · a₆
a₇ = -3/4 × -243/1024
a₇ = 729/4096
There are different definitions of "whole numbers".
Some define it as an integer (i.e. positive or negative) [some dictionaries]
Some define it as a non-negative integer. [most math definitions]
We will take the math definition, i.e. 0<= whole number < ∞
To find pairs (i.e. two) whole numbers with a sum of 110, we start with
0+110=110
1+109=110
2+108=110
...
54+56=110
55+55=110
Since the next one, 56+54=110 is the same pair (54,56) as 54+56=110, we stop at 55+55=110 for a total of 56 pairs.
The answer is: 
The explanation is shown below:
1. Cynthia rounds the number, which is identified as
, to one decimal place and the result is 6.3.
2. Based on this, we know that
could have been between 6.25 and 6.35. Therefore, the error interval for
is given by:

Where
indicates that the value 6.25 is included and
indicates that the value 6.35 is not included (Because if
had been exactly 6.35, Cynthia would round up to 6.4).
Perpendicular lines have slopes that are negative reciprocals. example: line a has a slope of 2/3, line b has a slope if -3/2 if they are perpendicular.