There should be no problem in finding the value of the unknown variable "b" in the equation given in the question.The equation is solvable for finding the value of "b" because it is the only unknown variable in the single equation that is given in the question.
45 = 3b + 69
Let us reverse both sides of the equation first. then, we get
3b + 69 = 45
3b = 45 - 69
3b = - 24
b = - (24/3)
= - 8
So from the above deduction, we can easily conclude that the value of b in the given equation is -8.
Answer:
B) 47.5%
Step-by-step explanation:
Refer to the normal distribution chart attached. If 130 is 2 standard deviations higher than the mean (ignore the numbers beneath the percentages), then by the empirical rule, this means that 34%+13.5%=47.5% of adults are between IQs of 100 and 130. Therefore, option B is correct.
Correct answer is: actual wingspan of airplane is 6 inches.
Solution:-
We are given that wingspan is 'a' feet and tail span is 'b' feet in a scale drawing.
And we are also given that tail span is 2 inches that is b=2 inches and 
Let us plugin the b value in above equation.

Multiplying with 2 on both sides.
a=3X2=6 inches.
Hence actual wingspan of airplane is 6 inches.