The sum of 7 times a number and one-fifth of it is 108. Find this number. (solution by equation)
一个数的7倍与它的五分之一的和是108，求这个数．(用方程解)
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">7 + (1/5)</gadget>
<output>36/5 = around 7.2</output>

<gadget id="calculator">108 / (36/5)</gadget>
<output>15</output>

<result>15</result>