Red = r
Blue = b
Green = g
Step 1: Write as algebraic equations.
r = b + 6
g = b - 4
Step 2: Merge the two equations together to form one, by adding them together.
r + g = b + b + 6 - 4
Step 3: Simplify.
r + g = 2b + 2
Step 4: Make b the subject.
2b + 2 = r + g
2b = r + g - 2
b = 0.5(r + g - 2)
ANSWER
b = 0.5(r + g - 2)
Given :
A 18-mile taxi ride takes 21 minutes and costs $12.60.
To Find :
The cost of a 39- mile taxi ride. What unit price do you need.
Solution :
Unit price per mile :

Cost of 39 mile taxi ride :

Therefore, unit price is $27.3 and unit price is $0.7 / mile .
Hence, this is the required solution.
Answer:
s = sqrt [ Σ ( x i - x ) 2 / ( n - 1 ) ]
Step-by-step explanation:
where s is the sample standard deviation, x is the sample mean, x i is the ith element from the sample, and n is the number of elements in the sample. And finally, the standard deviation is equal to the square root of the variance.
3 because 7*3=21,...........