Question

On Tuesday, the high temperature was 54° F. This was 10% lower than the high temperature on Monday. What was the temperature on Monday?

Answer 1

From the question, we can say that the high temperature on Monday minus its 10%, equals the high temperature on Tuesday (54° F). Let's call T the temperature on Monday:

$T-0.1\cdot T=54$

The term 0.1*T represents the 10% of T.

Solving the equation:

$\begin{gathered} T(1-0.1)=54 \\ \\ T\cdot0.9=54 \\ \\ T=\frac{54}{0.9} \\ \\ T=60 \end{gathered}$

Then, the temperature on Monday was 60° F.