Question

What is the best estimate for 7.8 x 37.86?A.46B.50C.300D.400

Answer 1

We can round both numbers to the nearest integer, therefore

`\begin{gathered} 7.8\rightarrow8 \\ 37.86\rightarrow38 \end{gathered}`

Therefore

`\begin{gathered} 7.8\cdot37.86\approx8\cdot38 \\ \end{gathered}`

And

`8\cdot38=304`

Therefore 7.8 x 37.86 is something near 300. The correct answer is the letter C.