Question

A recipe for a cake instructs you to bake it at 220° C for 45 minutes. How many degrees Fahrenheit is this?

Answer 1

This is an exercise on Thermometric scales.

We have as data:

• T = 220 °C
• T = °F ??

We apply the following formula:

`\large\displaystyle\text{$\begin{gathered}\sf ^(\circ)F=(9)/(5)\ ^(\circ)C+32 \end{gathered}$}`

We substitute data in the formula:

`\large\displaystyle\text{$\begin{gathered}\sf ^(\circ)F=(9)/(5)*220+32 \end{gathered}$}`

First multiply 9 x 220, then the result of this division is divided by 5.

`\large\displaystyle\text{$\begin{gathered}\sf =396+32 \ \ \to \ \ [Add] \end{gathered}$}`

`\boxed{\large\displaystyle\text{$\begin{gathered}\sf =428 \ ^(\circ)F \end{gathered}$}}`

Therefore the cake recipe that should be baked at 220 °C for 45 minutes, on the Fahrenteir scale is 428 °F. Which indicates that it will be very hot.