To solve this, we use the z test.
The formula:
z = (x – u) / s
where x is sample value = 20, u is the mean = 15, and s is
the standard deviation = 2.5
z = (20 – 15) / 2.5
z = 2
Since we are looking for values greater than 20, this is
right tailed test. We use the standard distribution tables to find for P.
P = 0.0228
Therefore:
number of students = 100 * 0.0228 = 2.28
<span>2 to 3 students will get greater than 20 measurement</span>
Answer:
The answer is 12ac^14/b^3
Answer:4x2−6x−4
Step-by-step explanation:
(4x+2)(x−2)
=(4x+2)(x+−2)
=(4x)(x)+(4x)(−2)+(2)(x)+(2)(−2)
=4x2−8x+2x−4
=4x2−6x−4
Distance = speed x time
2.257 x 9.111 = 20.563527 or 20
There are 12 inches in a foot, so 9ft = 108in. Also, 80% = 0.8. Therefore the formula is:
h(n) = 108 * 0.8^n.
To find the bounce height after 10 bounces, substitute n=10 into the equation:
h(n) = 108 * 0.8^10 = 11.60in (2.d.p.).
Finally to find how many bounces happen before the height is less than one inch, substitute h(n) = 1, then rearrage with logarithms to solve for the power, x:
108 * 0.8^x = 1;
0.8^x = 1/108;
Ln(0.8^x) = ln(1/108);
xln(0.8) = ln(1\108);
x = ln(1/108) / ln(0.8) = -4.682 / -0.223 = 21 bounces