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if n(a) = 37, n(b) = 50, and a is subsets of b, find n(aub).

n(B)=21.

Step-by-step explanation:

n(AUB) means the the number of elements in both A & B. And that includes                  the ones in common too.

n(A∩B) means the ones that in common.

n(A-B) refers to the elements that belong to A alone. That means the elements in A excluding the common elements.

n(B) is the number of elements that belong to B and that includes the common ones too.

Now coming to your question.

The total number of elements that can fit in both the sets is 36.

While the number of common elements is 16.

And also given that n(A-B)=15.

Now according to the definitions aboven(A) should include the ones that belong exclusively to A alone and also the ones in common.

So,

n(A)=n(A-B)+n(A∩B)

       =15+16

       =31

Therefore, n(A) is 31.

Now when n(AUB) is 36 and n(A) is 31, it is clear that the elements exclusive  to B alone is 5, i.e.36-31.  

Now n(B)=n(A∩B)+n(B-A)

Therefore, n(B) is 16+5 = 21.

n(B)=21.

- 70

this is the answer for you hope it

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.