The answer is 25 13/20 square feet.
In order to complete this operation, it is first best to change your mixed numbers into improper fractions.
7 1/8 = 57/8
7 1/5 = 36/5
Now that we have these, we can put them into the triangle formula.
A = 1/2bh
A = (1/2)(57/8)(36/5)
A = 1026/40
You can then simplify this fraction by dividing the top and bottom by a factor of 2.
A = 513/20
Then, because we know 20 goes into 500, 25 times, we can pull that out and be left with a remainder of 13/20.
A = 25 13/20
Short Answer: 18 minutes
Remark
The answer to this problem is less than the smallest time of the two people working together. that fact lets out C and D (38 minutes and 75 minutes). Now you have to choose 15 minutes and 18 minutes. There's a method. No guessing needed.
Givens
Let the time for Sophie = S
Let the time for Simon = M
Let the job to completion = 1
S = 45 minutes
M = 30 minutes
Step One
Convert minutes to hours.
45 minutes = 45 / 60 = 3/4 hour = 0.75 hour
30 minutes = 30 / 60 = 1/2 hour = 0.50 hour
Step Two
Set up the Equation
The formula is a form of job / hour.
Let the time = t that they both have to work
job = 1 in these problems.
1/S + 1/M = 1/t
1/0.75 + 1/0.5 = 1/t
Solve
1 ÷ 0.75 = 1.33333
1 ÷ 0.5 = 2
1.3333 + 2 = 3.33333
3.3333 = 1 / t Multlply both sides by t
3.3333*t = 1
t = 1 / 3.333333333
t = 0.3 of an hour
1 hour = 60 minutes
0.3 hours = x Cross Multiply
x = 60 * 0.3
x = 18 minutes
Answer working together it took them 18 minutes <<<<<
Applying a dilation centered at the origin with scale factor 
has the effect of multiplying both coordinates of a point by :
So, in your case, the coordinates of the points double:
Answer:
0.1338 to the nearest ten thousandth.
Step-by-step explanation:
40 / 299
= 0.1337792642
