Number defective=4
number of non-defective=total-defective
=20-4
=16
the questions asked for 1 defective
so we choose only 1 defective from 4 defective items
4C1
and for 1 non-defective
we choose only 1 non-defective from 16 non-defective items
16C1
we choose 2 items from 20 items
so 20C2
answer:
probability= [(4C1) * (16C1)] /(20C2)
=32/95
The equation in slope-intercept form for the line that passes through the point ( -1 , -2 ) and is perpendicular to the line − 4 x − 3 y = − 5 is 
<em><u>Solution:</u></em>
<em><u>The slope intercept form is given as:</u></em>
y = mx + c ----- eqn 1
Where "m" is the slope of line and "c" is the y - intercept
Given that the line that passes through the point ( -1 , -2 ) and is perpendicular to the line − 4 x − 3 y = − 5
Given line is perpendicular to − 4 x − 3 y = − 5
− 4 x − 3 y = − 5
-3y = 4x - 5
3y = -4x + 5

On comparing the above equation with eqn 1, we get,

We know that product of slope of a line and slope of line perpendicular to it is -1

Given point is (-1, -2)
Now we have to find the equation of line passing through (-1, -2) with slope 
Substitute (x, y) = (-1, -2) and m = 3/4 in eqn 1



Thus the required equation of line is found
When expanding number, we should separate the numbers according to the places like the number 275 written in expanded form 200+70+5. So, in this question we must likely done like this. The number is 39,005 the sum that is written on expanded form is 30,000+9,000+5.