Answer all the questions below and press submit to see how many you got right.
Count : To count means to find out the number of objects by adding one for every object.
Matrix : A $m\times n$ matrix is a rectangular arrangement of $m\cdot n$ numbers into $m$ rows and $n$ columns. For example $\begin{pmatrix}1&2&3\\4&5&6\\\end{pmatrix}$ is a $3\times 2$ matrix. $A_{ij}$ refers to the element of $A$ in the i-th row and j-th column.
Skip count : Skip counting refers to repeatedly adding the same number to a starting number. For example skip counting in twos starting at 3 results in 3, 5, 7, 9... Skip counting in threes starting in 1 results in 1, 4, 7, 10,...
How many X are in $\begin{matrix}X&X&X\\X&X&X\\X&X&X\\\end{matrix}?$
Number : A number $x$ is a mathematical symbol representing a quantity.
How many X are in $\begin{matrix}X&X&X&X\\\end{matrix}$?
How many numbers are in $\begin{matrix}1&2\\3&4\\5&6\\7\end{matrix}?$