1. The five-number summary for all student scores on an exam is 40, 60, 70, 75, 79.

Suppose 100 students took the test.

How many STUDENTS had scores between 40 and 70?

2. Suppose we know that the mean heart disease death rate is 200 per 100K people and is normally distributed across 27 countries. Suppose we also know that the greatest death rate reported is 220 per 100K and the lowest death rate reported is 180 per 100K. What should be a statistically-savvy person's best guess as to the SD of this distribution?

12cm

the answer is d

the polynomial is a perfect square trinomial of the form a^2-2ab+b^2:

option a. true

step-by-step explanation:

9x^2-12x+4

comparing with the form a^2-2ab+b^2

1.) a^2=9x^2

solving for a: square root both sides of the equation:

sqrt(a^2)=sqrt(9x^2)

a=sqrt(9) sqrt(x^2)

a=3x

2.) b^2=4

solving for b: square root both sides of the equation:

sqrt(b^2)=sqrt(4)

b=2

to be a perfet square trinomial 2ab must be equal to 12x. let's check:

2ab = 2 (3x) (2)

2ab = 12x

correct

hm let me think hm think think hm think yes