The amount of time that three people worked on a special project was in the ratio of 2 to 3 to 4. If the project took 90 hours, how many more hours did the hardest working person work than the person who worked the least?
Choose the correct choice from the following choices
A) 18 hours B) 22 hours C) 25 hours D) 26 hours E) 20 hours
Let the persons be A, B, C.   Hours worked:   A = 2*90/9= 
<gadget id="calculator">2*90/9</gadget>
<output>20</output>
20 hours   B= 3*90/9= 
<gadget id="calculator">3*90/9</gadget>
<output>30</output>
30 hours   C= 4*90/9= 
<gadget id="calculator">4*90/9</gadget>
<output>40</output>
40 hours   C is the hardest worker and A worked for the least number of hours. So the difference is  40-20= 
<gadget id="calculator"> 40-20</gadget>
<output>20</output>
20 hours.   Answer : 20 hours
<result>E</result>
The amount of time that three people worked on a special project was in the ratio of 2 to 3 to 4. If the project took 90 hours, how many more hours did the hardest working person work than the person who worked the least?