Mr. Rhee traveled 90 miles at 60 miles per hour to visit his parents on the way home he was caught in heavy traffic so that the average speed for the entire trip was 45 miles per hour. how fast did mr.rhee travel on the way home in miles per hour?

Answer:

Amy can choose from 60 possible passwords.

Solution:

Given that the two-letter password is from the letters A, B, C, D, E and F

Total number of letters = 6  

The password is a two digit letter and repetition of letters is not allowed.

Method 1:

\therefore The number of ways of obtaining an ordered subset of r elements from a set of n elements is given by

So, the total possible password = = =

On cancelling the in numerator and denominator we get,

Here we get, = 30  possible passwords

Method 2:

There are 6 possible choices for the first term of the password and 5 choices for the second term (i.e. leaving the selected letter of the term)

So,

Answer:

30

Step-by-step explanation:

6 choices for the 1st, then 5 choices for the 2nd, so: 6*5=30

or  nPk=n!/(n-k)!  with n=6 and k=2

Put it simply each letter can be combined with 5 diffrent letters and with 6 total letters 6x5=30

The value of x will be equal to 42.

What is an expression?

Expression in maths is defined as the collection of the numbers variables and functions by using signs like addition, subtraction, multiplication, and division.

Numbers (constants), variables, operations, functions, brackets, punctuation, and grouping can all be represented by mathematical symbols, which can also be used to indicate the logical syntax's order of operations and other features.

The expression 7x = 42 for the value of x will be solved as below:-

7x = 42

x = 42 / 7

x = 6

Therefore, the value of x will be equal to 42.

To know more about an expression follow

brainly.com/question/723406

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