Step-by-step explanation:
The plumber's daily earnings have a mean of $145 per day with a standard deviation of
$16.50.
We want to find the probability that the plumber earns between $135 and
$175 on a given day, if the daily earnings follow a normal distribution.
That is we want to find P(135 <X<175).
Let us convert to z-scores using

This means that:

We simplify to get:

From the standard n normal distribution table,
P(z<1.82)=0.9656
P(z<-0.61)=0.2709
To find the area between the two z-scores, we subtract to obtain:
P(-0.61<z<1.82)=0.9656-0.2709=0.6947
This means that:

The correct choice is C.
3,000 yd3 = 200 dtl
Chapter 1: Problem Solving 17 / 21
Rates Question
12 A highway had a landslide, where 3,000 cubic yards of material fell on the road, requiring 200 dump truck loads to clear. On another highway, a slide left 40,000 cubic yards on the road. How many dump truck loads would be needed to clear this slide?
3,000 yd3 = 200 dtl
40,000 yd3 × 200 dtl = 2,667 dtl
3, 000 yd3
L = A/W
Length equals area divided by width
Area of rectangle = length x width If length is constant, say c and width is variable, say x Area of rectangle = y = cx This means Area will vary linearly with width and will represent a line with slope... hope I helped