Step-by-step explanation:
The difference in the formula of population and sample variance can be explained as:
Population variance is said to be the value of variance that is calculated from population data, whereas sample variance refers to the variance calculated from sample data. This is the reason why value of denominator in the formula for variance in case of sample data is ‘n-1’, while it is ‘n’ for population data. Hence, the result of both variance and standard deviation derived from sample data is larger than those found out from population data.
Answer:
45 minutes
Step-by-step explanation:
let after t hours they meet after the second runner starts.
15 minutes=1/4 hour.
6(t+1/4)=8t
6t+6/4=8t
8t-6t=6/4
2t=3/2
t=3/2* 1/2=3/4 hours=45 minutes
Answer:
20 percent
Step-by-step explanation:
100(%) (all 5 balls) ÷ 5 = 20(%)
(-5x ⁵+14)-(11x ²+1+11x ⁵)
Like terms: -5x ⁵-11x ⁵ = -16x ⁵
Like terms also: 14-1 = 13
Simplified all together: -16x ⁵ - 11x ²+ 13
(Always put highest degree first)
Answer:
y = 60
Step-by-step explanation:
From the information we get:
x quantity of 4 dollars coffee used in the mix
y quantity of 7 dollars coffee used in the mix
For the quantity of coffee to be sold a 7 $/pound ( 90 pounds)
Then 6*90 = 540 $
Therefore
x + y = 90 and
4*x + 7*y = 540
A two equations system we solve for x and y
y = 90 - x
4*x + 7* ( 90 - x ) = 540
4*x + 630 - 7*x = 540
- 3*x = - 90
x = 30 pounds and
y = 90 - 30
y = 60
We should use 60 pounds of the seven $ coffee
