Xavier starts from P towards Q at a speed of 90 kmph and after every 12 mins increases his speed by 10 kmph. If the distance between P and Q is 51km, then how much time does he take to cover the distance?  Choose the correct choice from the following answers:
A) 30	B) 32	C) 30	D) 36	E) 40
first 12min = 90 *12/60= 
<gadget id="calculator">90 *12/60</gadget>
<output>18</output>
18km   2nd 12min= 100*12/60= 
<gadget id="calculator">100*12/60</gadget>
<output>20</output>
20km   3rd 12 min= 110*12/60= 
<gadget id="calculator">110*12/60</gadget>
<output>22</output>
22 km   TOTAL time   12 *3= 
<gadget id="calculator">  12 *3</gadget>
<output>36</output>
36 min   36
<result>D</result>
Xavier starts from P towards Q at a speed of 90 kmph and after every 12 mins increases his speed by 10 kmph. If the distance between P and Q is 51km, then how much time does he take to cover the distance?