QUESTION:
The code for a lock consists of 5 digits (0-9). The last number cannot be 0 or 1. How many different codes are possible.
ANSWER:
Since in this particular scenario, the order of the numbers matter, we can use the Permutation Formula:–
- P(n,r) = n!/(n−r)! where n is the number of numbers in the set and r is the subset.
Since there are 10 digits to choose from, we can assume that n = 10.
Similarly, since there are 5 numbers that need to be chosen out of the ten, we can assume that r = 5.
Now, plug these values into the formula and solve:
= 10!(10−5)!
= 10!5!
= 10⋅9⋅8⋅7⋅6
= 30240.
Answer:
x ≈ 14.87
Step-by-step explanation:
Using Pythagoras' identity in the right triangle.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
x² = 10² + 11² = 100 + 121 = 221 ( take the square root of both sides )
x =
≈ 14.87 ( to the nearest hundredth )
<u>Story Problem</u>
Mr. Bill Gates bought a house in Italy for
and a house in Canada for
. What is the total cost of the two houses?
we know that
The total cost is the sum of the cost each house
so

therefore
the answer is
The total cost is 