Mathematics Past Questions and Answers

If the variance of 3+x, 6, 4, x and 7-x is 4 and the mean is 5, find the standard deviation

A \(\sqrt{3}\)
B 2
C 3
D \(\sqrt{2}\)

Question 77:

\(\begin{array}{c|c} Score & 3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 \\ \hline Frequency & 1 & 0 & 7 & 5 & 2 & 3 & 1 & 1 \end{array}\)
The table above shows the scores of 20 students in further mathematics test. What is the range of the distribution?

A 7
B 6
C 3
D 10

Question 78:

In how many ways can a student select 2 subjects from 5 subjects?

A \(\frac{5!}{3!}\)
B \(\frac{5!}{2!2!}\)
C \(\frac{5!}{2!3!}\)
D \(\frac{5!}{2!}\)

Question 79:

In how many ways can 3 seats be occupied if 5 people are willing to sit?

A 60
B 20
C 5
D 120

Question 80:

What is the probability that an integer x \((1 \leq x \leq 25)\) chosen at random is divisible by both 2 and 3?

A \(\frac{1}{25}\)
B \(\frac{1}{5}\)
C \(\frac{4}{25}\)
D \(\frac{3}{4}\)