Question

marcus tried to solve in eqaution step by step.2.5b=52.5b/2.5=5/2.5 step1b=3 step 2find marcus's mistake.step1step2marcus did not make a mistake

Answer 1

We can redo the steps as:

$\begin{gathered} 2.5b=5 \\ \frac{2.5b}{2.5}=\frac{5}{2.5} \\ b=2 \end{gathered}$

He made a mistake in step 2, when calculating 5/2.5. The result is 2, not 3.

Answer: step 2.