There are some online calculators
Answer:

Step-by-step explanation:
Let
x -----> the number of minutes
y ----> the balloon's height in feet
we know that
The linear equation in slope intercept form is equal to

where
m is the slope
b is the y-coordinate of the y-intercept
In this problem we have that
The slope is equal to
----> is negative because is a decreasing function

Remember that the y-intercept is the value of y when the value of x is equal to zero
In this context the y-intercept is the height of the balloon when the time is equal to zero (initial height)
substitute

Answer:
3:2
Step-by-step explanation:
Answer:

And we can find the individual probabilities using the probability mass function
And replacing we got:

Step-by-step explanation:
Previous concepts
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
Solution to the problem
Let X the random variable of interest "number of automobiles with both headligths working", on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
And for this case we want to find this probability:

And we can find the individual probabilities using the probability mass function
And replacing we got:

Answer:
x = 9
Step-by-step explanation:
50+80+(6x-4)=180 (ANGLE SUM PROPERTY)
130 +(6x-4)=180
6x-4=180-130
6x-4=50
6x=50+4
x=54/6
x = 9