This is just an example i came up with randomly:
Emma is going somewhere for vacation. Emma has been traveling for 6 hours and in those 6 hours, she has travelled 36 miles. How many miles did she travel in one hour?
Subtract 12x from 84x = 72x
Answer:
25 ft
Step-by-step explanation:
The diagram shows two triangles that are similar. Similar triangles have equal angles and sides that are proportional to each other. Since the base of each triangle is given, we can find the proportion of the sides:

Given the ratio of the smaller to larger triangle, we can set up a proportion to find the missing height of the larger triangle:
, where 'x' represent the height of the tree
cross-multiply: x = (5)(5) or 25 ft
Answer:
34.87% probability that all 5 have a wireless device
Step-by-step explanation:
For each student, there are only two possible outcomes. Either they own a wireless device, or they do not. The probability of a student owning a wireless device is independent from other students. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
81% of students own a wireless device.
This means that 
If 5 students are selected at random, what is the probability that all 5 have a wireless device?
This is P(X = 5) when n = 5. So


34.87% probability that all 5 have a wireless device
The answer is c: y = 10.29(0.7)^x.