The fourth proportional to 12, 14 and 18 is?
Choose the correct answer.
A) twenty one
B) 66
C) 77
D) 88
E) 12
(14* 18) /12= 
<gadget id="calculator">(14* 18) /12</gadget>
<output>21</output>
21   twenty onenswer: twenty one
<result>A</result>
The fourth proportional to 12, 14 and 18 is?