For a given frequency distribution,$\Sigma f_{i} u_{i} = -13$,$n = \Sigma f_{i} = 100$,$A = 62.5$ and $c = 15$. Then,mean $\bar{x} = \dots$

For a given frequency distribution,$A = 450, c = 100, \Sigma f_{i} u_{i} = -20$ and $\Sigma f_{i} = 20$. Then,the mean $\bar{x} = \ldots$

In a maths test taken by $40$ students,the average score of $30$ boys is $16$ and the average score of $10$ girls is $12$. Which of the following gives the average score of the whole class?

The mode of the following data is $33 \frac{1}{3}$ and the total frequency is $100$. Find the missing frequencies $x$ and $y$.

Class	$0-10$	$10-20$	$20-30$	$30-40$	$40-50$	$50-60$
Frequency	$7$	$12$	$x$	$28$	$y$	$9$

$\frac{Z-M}{M-\bar{x}}=\ldots \ldots \ldots \ldots$

The mode of the observations $4, 5, 6, 3, 4, 3, 3, 2, 3, 5$ is $\ldots \ldots \ldots \ldots .$