#### Answer

$37^{\circ}~C$

#### Work Step by Step

$C = \frac{5}{9}(F-32)$
We can use this formula to convert from Fahrenheit to Celsius. It is given in the question that $F = 98.6$ since the temperature on the Fahrenheit scale is $98.6^{\circ}~F$.
$C = \frac{5}{9}(F-32)$
$C = \frac{5}{9}(98.6-32)$
$C = \frac{5}{9}(66.6)$
$C = 37$
The temperature on the Celsius scale is $37^{\circ}~C$