A runs twice as fast as B and gives B a start of 64m.How long should the racecourse be so that A and B might reach in the same time? Choose the correct option:
A) 75 m.
B) 128 m.
C) 150 m.
D) 100 m.
E) None of the above
ratio of speeds of a and b is 2:1   b is 64m away from a but we know that a covers 1 meter(2-1) more in every second than b   the time taken for a to cover 64m is   64/1= 
<gadget id="calculator">  64/1</gadget>
<output>64</output>
64m   so the total time taken by a and b to reach=2*64= 
<gadget id="calculator">2*64</gadget>
<output>128</output>
128m   ANSWER:128 m.
<result>B</result>
A runs twice as fast as B and gives B a start of 64m.How long should the racecourse be so that A and B might reach in the same time?