The mean mass of $13$ textbooks is $875$ grams, and $n$ novels have a total mass of $13706$ grams. Find the mean mass of a novel, given that the textbooks and novels together have a mean mass of $716.6$ grams.

Nine values are $7, 13, 28, 36, 13, 29, 31, 13$ and $x.$

Write down the value of the measure of central tendency that can be found without knowing the value of $x.$

Nine values are $7, 13, 28, 36, 13, 29, 31, 13$ and $x.$

If it is known that $x$ is greater than $40,$ which measure of central tendency other than mode can be found and what is its value?

Nine values are $7, 13, 28, 36, 13, 29, 31, 13$ and $x.$ If the remaining measure of central tendency is $25,$ find the value of $x.$

For the data shown in the following table, $x$ has a mean of $7.15.$

Find the mean value of $y$ given in the following table.

For the data shown in the following table, $x$ has a mean of $7.15.$

Find a calculated estimate of the mean value of $z$ given in the following table.

The table below shows the number of books read last month by a group of children.

If the mean number of books read is exactly $3.75,$ find the value of $q.$

The table below shows the number of books read last month by a group of children.

Find the greatest possible value of $q$ if: the modal number of books read is $4$

The table below shows the number of books read last month by a group of children.

Find the greatest possible value of $q$ if: the median number of books read is $4.$