Question

Fill in the blanks to make the statement true:$(-4)+[15+(-3\left)\right]=[-4+15]+\_\_\_\_\_\_$.

Answer 1

Compute the required value:

Suppose that $x$ is the missing number. Then,

$$\begin{gathered} (–4)+[15+(–3\left)\right]=[–4+15]+x \\ (–4)+[15–3)]=[–4+15]+x \\ (-4)+[12]=[11]+x \\ 8=11+x \end{gathered}$$

$$\begin{gathered} x=8-11 \\ x=-3 \end{gathered}$$

Hence the required statement is $(–4)+[15+(–3\left)\right]=\left[\right(–4)+15]+(-3)$.