Question

Find ‘C’ as the subject of formula, for${\rm{F = }}\dfrac{9}{5}C + 32$
a) $C = \dfrac{5}{9}({\rm{F - 32}})$
b) $C = \dfrac{9}{5}({\rm{F - 32}})$
c) $C = \dfrac{5}{9}({\rm{F + 32}})$
d) None of the above

Answer 1

Hint: In this question you need to express ‘C’ in terms of ‘F’. So, keeping ‘C’ at one side (LHS or RHS) shifts all other expressions to the other side (LHS or RHS).

Complete step-by-step answer:
In this question the given equation is,
$ \Rightarrow {\rm{F = }}\dfrac{9}{5}C + 32$
Now we have to express ‘C’ in terms of ‘F’,
Subtracting 32 on both sides,
$ \Rightarrow {\rm{F - 32 = }}\dfrac{9}{5}C$
Multiplying $\dfrac{5}{9}$ on both sides,
$ \Rightarrow \dfrac{5}{9}({\rm{F - 32) = }}C$
$\therefore {\rm{ }}C{\rm{ = }}\dfrac{5}{9}({\rm{F - 32)}}$
Thus, option (A) is the correct answer.

Note: In this type of question concentrates more on positive sign (+) and negative sign (-).