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

Gundra Kiran
PLUS
Gundra Kiran
Courses Plus Student 5,931 Points
Posted by Gundra Kiran
Gundra Kiran
Courses Plus Student 5,931 Points

Please guide me

I did whatever is asked but I am unable to figure out what is required

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

1 Answer

David Lacedonia
David Lacedonia
13,627 Points
David Lacedonia
David Lacedonia
13,627 Points

Create a float variable called runningTotal. Then, create a for in loop which iterates through the array you created in step 1. When the loop finishes running, the value of 'average' should be the average of the values contained in temp. (NOTE: To convert an NSNumber, 'x', to a float, use [x floatValue] )

  1. The 'runningTotal' variable must be created outside the for loop, because is where you store the sum of the elements in the temps array
  2. Average is the sum of a list of numbers divided by the number of numbers in the list (runningTotal / temps.count) 
NSArray *temps = @[@75.5,@83.3,@96,@99.7];
float average;
float runningTotal;
for (NSNumber *temp in temps) {
  runningTotal += [temp floatValue];
}
average = runningTotal / temps.count;