How many even k-digit numbers can be constructed out of the digits 3, 4, 5, 6, and 7? a. Assume first that you may use the same digit again.
b. Assume that you cannot use a digit more than once.

A. 1562 numbers , B. 130 numbers

Step-by-step explanation:

A) Using same digit again

1 digit nos = 2 ( ie 4 , 6 )

2 digit nos = 5  (ie any no) x 2 ( ie 4 ,6 )

Similarly

3 digit nos = 5 x 5 x 2

4 digit nos = 5 x 5 x 5 x 2

5 digit nos = 5 x 5 x 5 x 5 x 2

Adding all 5 equations

Total = 2 + 10 + 50 + 250 + 1250  = 1562

B) Cant use a digit more than once

1 digit nos = 2 ( ie 4 , 6 )

2 digit nos = 4 ( ie any no other than 4 or 6) x 2  ( ie 4 , 6 )

Similarly

3 digit nos = 4 x 3 x 2

4 digit nos = 4 x 3 x 2 x 2

5 digit nos = 4 x 3 x 2 x 1 x 2

Adding all five equations

Total = 2 + 8 + 24 + 48 + 48 = 130

4+n=5

step-by-step explanation:

this is because the four is four hours and the n represents the 1 extra hour over the weekend.

b= i'm srry i don't know that one.

4+n=5 n=1 because if vernon plays 5 hours a week then 4+1=5 hours.

hope this : )

25 questions , because they start with 100.  

350-100=250 .  

. 250/10=25

step-by-step explanation:

first take off 100, then what x 10 = 250? that is your answer. (25)