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iOS Object-Oriented Objective-C Tying it All Together Cumulative Review

Posted by Alex Wilson
Alex Wilson
1,935 Points

How to find the average of an array?

I have figured most of the challenge out but I can not figure out how to get the average.

-Thanks

variable_assignment.mm 
NSArray *temps =  @[@"75.5",@"83.3",@"96",@"99.7"];
float average;
float runningTotal = 0;
for (NSNumber *monkey in temps){


};

1 Answer

Cindy Lea
PLUS
Cindy Lea
Courses Plus Student 6,497 Points
Cindy Lea
Cindy Lea
Courses Plus Student 6,497 Points

First, you need to add all the values, then once totals are done you divive total by number of items in array:

NSArray *temps = @[@75.5, @83.3, @96, @99.7]; 
float average ; 
float runningTotal ;

for (NSNumber *itemsInTemp in temps) {
  runningTotal += [ itemsInTemp floatValue] ;
}

average = runningTotal/temps.count;