Answer:
[tex]A.\ 1\frac{17}{30}\ hours[/tex]
Step-by-step explanation:
[tex]Let\ second\ jet\ overtake\ first\ in\ x\ hours.\\\\[/tex]
Distance covered by first jet:
[tex]Speed\ of\ first\ jet=564\ km/h\\\\Time=x+\frac{1}{2}\\\\Distance\ covered=speed\times time\\\\Distance\ covered=564\times (x+\frac{1}{2})=564x+564\times \frac{1}{2}\\\\Distance\ covered=564x+282[/tex]
Distance covered by second jet:
[tex]Speed\ of\ second\ jet=744\ km/h\\\\Time=x\\\\Distance\ covered=speed\times time\\\\Distance\ covered=744\times x\\\\Distance\ covered=744x[/tex]
[tex]Distance\ covered\ by\ both\ the\ jet\ in\ x\ hours\ is\ equal.\\\\744x=564x+282\\\\744x-564x=282\\\\180x=282\\\\x=\frac{282}{180}=\frac{6\times 47}{6\times 30}\\\\x=\frac{47}{30}\ hours\\\\x=1\frac{17}{30}\ hours[/tex]