In one hour, Addison mountain's temperature will decrease to 3/4  of its temperature. If the current temperature of the mountain is 84 degrees, what will the temperature decrease by?
In one hour, Addison mountain's temperature will decrease to 3/4 of the temperature it is now, meaning the temperature will decrease to 3/4*84=
<gadget id="calculator">3/4*84</gadget>
<output>63</output>
63 degrees.
The temperature decrease will be 84-63=
<gadget id="calculator">84-63</gadget>
<output>21</output>
21 degrees.

<result>21</result>