Answer:
Step-by-step explanation:
This is a Combination (as in permutation vs combination) question the symbol (n r) refers to "n choose r". This is sometimes written as nCr
i.e the question is asking you to find how many combinations each will yield when you chose r items from n item without repetition and order does not matter.
I will only do the first question for you and you can just follow the same steps to solve the rest of the questions.
Recall that

Consider question a) we are given (5 1) or ₅C₁
we can see that n = 5 and r = 1
If we substitute this into the formula:
₅C₁ = (5!) / [ (1!)(5- 1)!]
= (5!) / [ (5- 1)!]
= (5!) / (4!)
= (5·4·3·2·1) / (4·3·2·1)
= 5
hence ₅C₁ = 5
This is problem of ratio and proportion. to solve this, fisrt is calculate the convertion factor.
so the house is 30 feet in actual and 4 in wide on drawing
30 feet / 4 in = 7.5 feet / inso in every inch in the drawing is equivalent to 7.5 feet on actual.
1.2 in ( 7.5 ft/ in) = 9 ft
1.6 in ( 7.5 ft/ in) = 12 ft
The Answer Is 600 Because The Number To The Right Is Less Than 4
(4x^2-25)/(2x-5)=14
Step-by-step explanation:
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