Answer:
Step-by-step explanation:
The total number of students is 350 + 50 + 225 + 375 = 1000.
There are 225 students in band only, as well as 50 students in both band and choir. So there are 275 students in band out of the total of 1000, or 27.5%.
There are 350 students in choir only, as well as 50 students in both choir and band. So there are 400 students in choir, 50 of whom are also in band. So the probability is 50/400, or 12.5%.
The probabilities are not the same.
Since the probabilities are not the same, the probability of being in band is affected by whether or not the student is in choir. So the events are not independent.
Answer:
1/4
Step-by-step explanation:
This is a ratio problem; the ratio of the length to width is constant (and therefore equal):
4 /6 = 15 / x
Now, with a ratio, we may do any allowable algebra operation: cross-multiply, invert both sides, multiply or divide both sides by the same amount, etc.
Let's cross-multiply:
4x = (15)(6)
x = 90/4
x = 22.5 in.
It looks a little less than 1/2 or 4/8, so probably 3/8 of the gas is left.
let y = x^2
4y^2 -21y + 20 = 0
solve for y
then substitute back in to get x
