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In a class 40% of the students take Math and 70% take Spelling. If 15% of the students take both Math and Spelling, what % of the students did not take either of the two subjects?

Answer 1

Only #5%# of the students did not take any of 2 mentioned subjects.

To calculate the amount of students which did not take any of those subjects first we have to calculate the amount of the students which took at least one subject. To do this we have to perform calculations:

#40/100+70/100-15/100=(40+70-15)/100=95/100#

The substraction comes from the fact that students which took both classes were calculated twice (once as Math students and once again as Spelling students)

Now if we have the amount of students which took at least one subject we have to substract this number from the whole class:

#100%-95%=100/100-95/100=5/100#

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Answer 2

Skylar Adams

35% of the students did not take either of the two subjects.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.