Question

During a 5​-year ​period, 32% of snowstorms in a certain city caused power outage Fifty-one of the snowstorms did not cause power outages. Find the total number of snowstorms in this city over the 5​-year period.

Answer 1

Answer:
Total number of snowstorms = 75 storms

Explanation:
We are given that:
32% of the snowstorms caused power outage
This means that we can get the percentages of the snowstorms that did not cause power outage as follows:
% of storms not causing outage = 100% - 32% = 68%

Now, we are given that the number of snowstorms that did not cause power outage is 51 
Assuming that the total number of storms is x, the equation would be as follows:
68% * x = 51
0.68x = 51
x = 51 / 0.68
x = 75 storms

Hope this helps :)

Answer 2

To answer this question you will consider that if 32% of the storms did cause outages, then 100% (all of them)-32%= 68% did NOT produce a power outage. We can say that 68% of the total is 51.

This can be written as 0.68 x = 51 where x is the total number of snowstorms. Divide both sides by 0.68 to solve for x. X = 75 snowstorms. Another way to do this is to use Ratios. See the attached page for the strategy.