$3+$ $=2+3$

$1+6=6+$_____

$1+$_____$=7+1$

Fill in the number in the boxes such that its double is the given number.

$$\begin{gathered} \underline{\underline{\begin{array}{cc}& \square \\ +& \square \end{array}} \\ 8 } \end{gathered}$$

Fill in the number in the boxes such that its double is the given number.

$$\begin{gathered} \underline{\underline{\begin{array}{cc}& \square \\ +& \square \end{array}} \\ 6 } \end{gathered}$$

Fill in the number in the boxes such that its double is the given number.

$$\begin{gathered} \underline{\underline{\begin{array}{cc}& \square \\ +& \square \end{array}} \\ 1 0 } \end{gathered}$$

Fill in the blank boxes correctly.

Combinations of $3$.

Number: $3$

The number of combinations: $4$

Fill in the blank boxes correctly.

Combination of $4$.

Number: $4$

The number of combinations: $5$

Fill in the blank boxes correctly.

Combinations of $5$.

Number: $5$

The number of combinations: $6$