Question

Ice point and steam point on a particular scale reads $10^\circ $ and $80^\circ $ respectively. The temperature on $^\circ F$ scale when temperature on new scale is $45^\circ $ is

• A. $50^{ \, o}F$
• B. $112^{o}F$
• C. $122^{ o}F$
• D. $138 \,{}^{o}F$

Answer 1

Answer: (C)

Relation between the two scales
$\frac{t - 10}{80 - 10}=\frac{F - 32}{212 - 32}$
$F-32=\frac{18}{7}\left(t - 10\right)$
$F=\frac{18}{7}\left(45 - 10\right)+32$
$F=122^{ \, o}F$