Answer:
(a) 
(b) 100
Step-by-step explanation:
Solving (a):
Given
Shape: Rectangle

Required
Calculate the perimeter.
Area is calculated as:

Where
and 
Substitute 64.8 for Area

Make L the subject:

Perimeter is calculated as:

Substitute 64.8/W for L


To solve further, we take the derivative of P and set it to 0, afterwards.

Set to 0

Collect Like Terms

Cross Multiply:

Divide through by 2

Take square roots


Recall that:

So:


The perimeter is:



Solving (b):
Given
((1 Group of 10 tenths) and (1 group of 8 tenths))/(6 groups of 3 tenths)
Required
Solve

So, the expression becomes:
((1 Group of
) and (1 group of
))/(6 groups of
)
This gives:
((1 Group of
) and (1 group of
))/(6 groups of
)
Group means product, so the expression becomes:

And, as used here means addition

Simplify:




Twelve attempts were made at making a basket
Answer:
You have to multiply the denorminator to both sides in order to make x the subject :


Answer:
0.42 is closest to the proportion of customer purchase amounts between $14.00 and $16.00
Step-by-step explanation:
Mean = 
Standard deviation = 
We are supposed to find the proportion of customer purchase amounts between $14.00 and $16.00
P(14<x<16)
Formula : 
At x = 14


Refer the z table for p value
P(x<14)=0.1922
At x = 16


Refer the z table for p value
P(x<16)=0.6141
P(14<x<16)=P(x<16)-P(x<14)=0.6141-0.1922=0.42
So, Option C is true
Hence 0.42 is closest to the proportion of customer purchase amounts between $14.00 and $16.00