Three numbers are in the ratio 3:5:7. The largest number is 35. What is the difference between smallest and largest number?
Choose the correct option:
A) 16  B) 18  C) 20  D) 22  E) 24
The three numbers are 3x, 5x, and 7x.   The largest number is 35 = 7*5, so x = 5.   The smallest number is   3*5= 
<gadget id="calculator">  3*5</gadget>
<output>15</output>
15.   35 - 15= 
<gadget id="calculator">35 - 15</gadget>
<output>20</output>
20   The answer is 20.
<result>C</result>
Three numbers are in the ratio 3:5:7. The largest number is 35. What is the difference between smallest and largest number?