What is the last digit of

Mathematics

2 answers:

Papessa [141]3 years ago

7 0

Answer:

Answer C. 5

Step-by-step explanation:

Product of Odd and Even Numbers

Any number ending in 5 is necessarily a multiple of 5. For example, 85, 1005, 12345 are all multiple of 5.

Any number ending in 0 is a multiple of 5 and even therefore, is a multiple of 10.

Any integer number multiplied by another number ending in 5 gives one of these possible results:

* A multiple of 5 if the number is odd

* A multiple of 10 if the number is even.

The given product 1*3*5*7*9*11*13 is a multiple of 5 because 5 is one of the factors, and since the rest of the factors are all odd numbers, then the result is a multiple of 5 and has its last digit of 5.

Answer C. 5

yKpoI14uk [10]3 years ago

4 0

Step-by-step explanation:

When a number is multiplied by 5, the last digit of the product must be 0 (mod 5).

=> Last digit = 0 or 5.

Since 0 is not an option here, the answer must be 5. (C)

You might be interested in

In a multiple choice quiz there are 5 questions and 4 choices for each question (a, b, c, d). Robin has not studied for the quiz

Ahat [919]

Answer:

a) There is a 18.75% probability that the first question that she gets right is the second question.

b) There is a 65.92% probability that she gets exactly 1 or exactly 2 questions right.

c) There is a 10.35% probability that she gets the majority of the questions right.

Step-by-step explanation:

Each question can have two outcomes. Either it is right, or it is wrong. So, for b) and c), we use the binomial probability distribution to solve this problem.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.\pi^{x}.(1-\pi)^{n-x}$

In which $C_{n,x}$ is the number of different combinatios of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And $\pi$ is the probability of X happening.

In this problem we have that:

Each question has 4 choices. So for each question, Robin has a $\frac{1}{4} = 0.25$ probability of getting ir right. So $\pi = 0.25$ . There are five questions, so $n = 5$ .

(a) What is the probability that the first question she gets right is the second question?

There is a 75% probability of getting the first question wrong and there is a 25% probability of getting the second question right. These probabilities are independent.

$P = 0.75(0.25) = 0.1875$