3:4 = G:B
1:5 = Mr. Smith's class: 7th Grade
2:7= 7th: Middle school
12 girls = 3 units
1 unit = 12/3= 4
Boys = 4x4= 16
<em>Whole class = 28 students</em>
Class : Grade = 1:5 <em> 7 = number of units in Mr. Smith's class</em>
28 = 1 unit
5 units= 28x5= 140 <em>There are 140 kids in the grade</em>
140 = 2 units
1 unit = 140/2= 70
70x7=490
<u><em>There are 490 students in the whole grade</em></u>
Answer:
80.0456<
<81.1210
Step-by-step explanation:
-Given the mean,
and
, the confidence interval can be calculated using the formula:

#We substitute our values in the formula to solve for CI:
![=\bar x\pm z\times \frac{\sigma}{\sqrt{n}}\\\\=\bar y\pm z_{0.05}\times \frac{s}{\sqrt{72}}\\\\=80.5833\pm 1.645\times \frac{2.77369}{\sqrt{72}}\\\\=80.5833\pm0.5377\\\\=[80.0456,81.1210]](https://tex.z-dn.net/?f=%3D%5Cbar%20x%5Cpm%20z%5Ctimes%20%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D%5C%5C%5C%5C%3D%5Cbar%20y%5Cpm%20z_%7B0.05%7D%5Ctimes%20%5Cfrac%7Bs%7D%7B%5Csqrt%7B72%7D%7D%5C%5C%5C%5C%3D80.5833%5Cpm%201.645%5Ctimes%20%5Cfrac%7B2.77369%7D%7B%5Csqrt%7B72%7D%7D%5C%5C%5C%5C%3D80.5833%5Cpm0.5377%5C%5C%5C%5C%3D%5B80.0456%2C81.1210%5D)
Hence, the confidence interval lies between 80.0456 and 81.1210
Answer:
y = 3x-9
Step-by-step explanation:
y = -1/3 x +2
The slope is -1/3
We want a line perpendicular to it
Perpendicular lines have negative reciprocal slopes
The new slope is -(-3/1) = 3
We have a slope m=3 and a point (5,6)
We will use point slope form to find the line
y-y-1 = m(x-x1)
y-6 = 3(x-5)
In slope intercept form
Distribute
y-6 = 3x-15
Add 6 to each side
y-6+6 = 3x-15+6
y = 3x-9
Let x = larger odd integer
then (x-2) is the smaller odd integer
Translate:
"sum of two consecutive odd integers is 80" means (x-2) + x = 80
2x -2 - 80
2x = 82
x = 41