Answer:
The area of the Iris is 4 times greater.
Step-by-step explanation:
Firstly, we have to realize that we cannot solve this problem without knowing the radius of the iris. because from the information given, the radius of the iris could well be the size of the galaxy and contract from width of 4mm to 2mm and we wouldn't know!
The average radius of the iris is 6mm, so we take this value.
Now, initially the width of the iris is 4mm, that means the radius of the pupil is:
Therefore it's area 
is:
When the iris contracts to 2mm, the radius of the pupil becomes:
Then it's area is :
To find how many times greater this final area is than the initial area, we just divide it by the initial area:
This is 4 times greater than the initial area.
Answer:
(C) Sample: the 120 students surveyed. Population: the 1200 students at the high school. Parameter of interest: the average number of hours a student at this high school sleeps per night.
Step-by-step explanation:
The correct answer is (C). The sample is a subset of the population, and the parameter is a characteristic of the population of interest.
Answer:
2x(7x - 3)(7x +3)
Step-by-step explanation:
Find common factors between the 2 numbers:
98x^3 - 18x
2x(49x^2 - 9)
now find what numbers multiplied together is 49, and find what numbers added together equals 0 and the product is 3, 7 times 7 is 49 and 3(-3) = 9 while 3 - 3 = 0 so:
2x(7x - 3)(7x +3)
Answer:
The original piece of wood is 108 cm
Step-by-step explanation:
From the given ratio, the shortest is of the ratio 5 and the longest is of the ratio 7
Let the original piece of wood be x
so the sum of the ratios will be;
5 + 6 + 6 + 7 = 24
the shortest length would be 5/24 * x
= 5x/24
the longest will be 7/24 * x = 7x/24
From the question;
7x/24 -5x/24 = 9
(7x-5x) = 24(9)
2x = 24(9)
x = (24 * 9)/2
x = 108 cm
