Answer:
y = 11
Step-by-step explanation:
y = 3(4) - 1
y = 12 - 1
y = 11
Step-by-step explanation:
since Poisson distribution parameter is not given so we have to estimate it from the sample data. The average number of of arrivals per minute at an ATM is
So probabaility for is
So expected frequency for is (or .
<span>4d + 12 = 4(d+3)
...............................</span>
A rug is to fit in a room so that a border of even width is left on all four sides.
If the room is 16 feet by 25 feet and the area of the rug is 220 square feet, how wide will the border
:
Let x = the width of the border around the rug
then
(25-2x) by (16-2x) the dimensions of the rug
:
The area equation
(25-2x)*(16-2x) = 220 sq/ft
FOIL
400 - 50x - 32x + 4x^2 = 220
:
Arrange as a quadratic equation
4x^2 - 82x + 400 - 220 = 0
:
4x^2 - 82x + 180 = 0
Simplify, divide by 2
2x^2 - 41x + 90 = 0
Factor
(2x - 5)(x - 18) = 0
Two solutions
2x = 5
x = 2.5 ft
and
x = 18 ft, obviously this not the solution
;
Border will be 2.5 ft
:
:
Check this by finding the dimension of the rug, and then the area
(25 - 2(2.5))*(16 - 2(2.5)) =
(25 - 5) * (16 - 5) =
20 * 11 = 220
Answer:
1:3:8
Step-by-step explanation:
The original ratio erasers:pens:pencils is 5:15:40. Since the greatest common factor is 5, we can divide all the numbers by 5.
Therefore the ratio is 1:3:8