Answer:
b c d e
Step-by-step explanation:
115 = 10X + 0.25(60)
115 = 10x +15 (this is the equation to use)
100=10x
x=10 hours
Answer:
To calculate the relative frequency, first we need to know what exactly is and how to calculate it.
Relative frequency is the ratio between the absolute frequency (how many repetitions have a specific outcome) and the total outcomes. Also, this type of frequency is used to show the representation that some data have over the whole distribution.
So, in this case, we need to just divide 13, which belongs to red marble's results, to 60 which is the total outcomes, as it's presented:
13redmarble Fr = -------------------------
60 totalmarbles
Normally, relative frequency is shown as a percentage multiplying this result by 100. Therefore, 22% is the approximate percentage of the relative frequency, which means that 22% is the representation of red marbles outcomes of the whole distribution, or we can say it as a probability: there's 22% of chances when someone extract a marble, it will be red.
X²+y²-2y=7
using the formula that links Cartesian to Polar coordinates
x=rcosθ and y=r sin θ
substituting into our expression we get:
(r cos θ)²+(r sin θ)²-2rsinθ=7
expanding the brackets we obtain:
r²cos²θ+r²sin²θ=7+2rsinθ
r²(cos²θ+sin²θ)=7+2rsinθ
using trigonometric identity:
cos²θ+sin²θ=1
thus
r²=2rsinθ+7
Answer: r²=2rsinθ+7