Answer:
a) 16%
b) 2.5%
Step-by-step explanation:
a)
The mean is 70 with standard deviation(SD) of 3 and you are asked to find out the percentage of staff that have <67(70-3 inch= mean - 1 SD) inch size, which means 1 SD below the mean (<-1 SD). Using 68-95-99.7 rule, you can know that 68% of the population is inside 1 SD range from the mean ( -1 SD to + 1 SD).
To put it on another perspective, there are 32% of the population that have < -1 SD and > +1 SD value. Assuming the distribution is symmetrical, then the value of < - 1 SD alone is 32%/2= 16%
b)
The question asks how many populations have size >76 inches, or mean + 2 SD (70+3*2 inch).
You can also solve this using 68-95-99.7 rule, but you take 95% value as the question asking for 2 SD instead. Since 95% of population is inside 2 SD range from the mean ( -2 SD to + 2 SD), so there are 5% of population that have < -2 SD and > +2 SD value. Assuming the distribution is symmetrical, then the value of > +2 SD alone is 5%/2= 2.5%
<h3>
Answer:</h3>
y=kx
Step-by-step explanation:
That's the formula for direct variation relationships!
The other two answers are nonsense and don't mean anything.
#5
57.8 can be rounded to 60 because 57.8 is closer to 60 than 50 and 81 is relatively close to 80. if we had to estimate the quotient, we would have
60 ÷ 80 = 0.75
#8
2.8 can be rounded to 3 because 2.8 is closer to 3 than it is to 2 and 6 can be left alone because it will make our division easier.
3 ÷ 6 = 0.5
#11
737.5 can be rounded to 700 and 9 can be rounded to 10.
700 ÷ 10 = 100
Answer:
x > -3

Step-by-step explanation:
Domain: input values (x-values)
Monotonic increasing: always increasing.
A function is increasing when its graph rises from left to right.
The graph of a quadratic function is a parabola. If the leading term is positive, the parabola opens upwards. The domain over which the function is increasing for a parabola that opens upwards is values greater than the x-value of the vertex.
<u>Vertex</u>
Standard form of quadratic equation: 

Given function:

Therefore, x-value of function's vertex:

<u>Final Solution</u>
The function is increasing when x > -3
