(2x^2 -5y)/(3x-y)
((2*2)^2-(5*-4))/((3*-4)-(-4))
(4^2+20)/(-12+4)
36/-8
-4.5
First, you have to set a system of equations to determine the number of fiction and of nonfiction books.Call f the number of fiction books and n the number of nonfiction books. Then 400 = f + n. And f = n + 40 => n = f - 40 => 400 = f + f - 40 => 400 - 40 = 2f => f = 360 / 2 = 180. Now to find the probability of picking two fiction books, take into account the the Audrey will pick from 180 fiction books out of 400, and Ryan will pick from 179 fiction books out of 399, so the probability will be<span> (180/ 400) * (179/399) = 0.20 (rounded to two decimals). Answer: 0.20</span>
168
You add 4, 1, and 2 to get 7. You put 4/7=x/294. Then you use proportions to solve for x.
7x=1176
x=168
Answer:
= 12 miles per hour
Step-by-step explanation:
This is a fraction equal to
30 miles ÷ 2.5 hours
We want a unit rate where
1 is in the denominator,
so we divide top and bottom by 2.5
30 miles ÷ 2.5
2.5 hours ÷ 2.5
=
12 miles
1 hour
=
12 miles
hour
= 12 miles per hour
<span>mean: ( 9 + 7 + 6.5 + 7.5 + 7 + 8 + 5 + 6 + 7.5 + 8 ) : 10 = 7.15Variance:(Sigma)² = ( 1.85² + 0.15² + 0.65² + 0.35² + 0.15² + 0.85² + 2.15² + 1.15² + 0.35² + 0.85² ) : 10 ≈ 1.15Answer: C ) 1.15</span>
