Answer:
37.8
Step-by-step explanation:
Simplify the EXPRESSION.
Answer:
324 cm²
Step-by-step explanation:
→ Work out perimeter of square
72 + 72 + 72 + 72 = 288
→ Work out the width of the rectangle
288 - (90 × 2) = 108
108 ÷ 2 = 54
→ Work out area of square
72 × 72 = 5184 cm²
→ Work out area of rectangle
90 × 54 = 4860 cm²
→ Minus the areas from each other
5184 cm² - 4860 cm² = 324 cm²
Answer:
About 95% of households have an income over $54,550
Step-by-step explanation:
95% is a probability of around 0.95
So we start by calculating the z-score with a probability of 0.95
We can use the standard normal distribution table for this
the z-score is -1.645
Mathematically;
z-score = (x-mean)/SD
-1.645 = (x-71,000)/10,000
10,000 * -1.645 = x-71,000
-16450 = x - 71000
x = 71,000 - 16450
x = 54,550
Mean number of errors in each page = 0.01
Mean number of errors in 100 pages = 0.01*100=1
It is possible to use the cumulative distribution function (CMF), but the math is a little more complex, involving the gamma-function. Tables and software are available for that purpose.
Thus it is easier to evaluate with a calculator for the individual cases of k=0,1,2 and 3.
The Poisson distribution has a PMF (probability mass function)


with λ = 1
=>




=>

or
P(k<=3)=
0.9810 (to four decimal places)