Answer:
35
Step-by-step explanation:
Here we see 5 black keys for every 7 white keys.
So the ratio is 5:7
If we need 49 white keys, find the amount we scale the original ratio by:
49/7 = 7
So we are scaling by a factor of 7.
The number of black keys would be 5 * the scale of 7. = 35
So there should be 35 black keys.
Answer is probably D
Here is how i did,
i can be wrong but thats how i figure it out
Answer:
h=3y+9
Step-by-step explanation:
We will write an expression using the y=mx+b format.
h in this case will be the height at any given year.
3 is the rate at which the three grows, y will represent any given year.
9 is the starting rate, or your y intercept.
Answer:
Fast car = 45.6
Slower car = 30.4
Step-by-step explanation:
Let the speed of the first car = x
Let the speed of the second car = y
Travelling towards each other.
x *1 + y*1 = 76 miles
x*5 - y*5 = 76 miles. This is kind of tricky. You have to understand that the first car that is 76 miles from the second car and makes up that 76 in 5 hours. The distance they both travel is subtracted out.
Divide by 5
x - y = 76/5
x - y = 15.2 The speeds differ by 15.2
x + y = 76
x - y = 15.2
2x = 91.2
x = 45.6
y = 76 - 45.6 = 30.4
When the two vehicles speeds are multiplied by 5, the difference is 76 km
Answer:
P(X<118.81)=0.0803
Step-by-step explanation:
Assuming the distribution for the mean life is approximately normal, with mean 120 months and variance 64 months^2, we can calculate the parameters for a sampling distribution with sample size = 89 computers.
The sampling distribution mean will be equal to the mean for a single computer:
The standard deviation will be adjusted by the sample size as:
With these parameters, we can calculate the z-score for X=118.81.
Then, the probability that the mean of a sample of 89 computers is less than 118.81 months is:
