A boat moves upstream at the rate of 1 km in 30 minutes and down stream 1 km in 12 minutes. Then the speed of the current is : Choose the correct choice from the following answers
A) 1.5 kmph	B) 2 kmph	C) 3 kmph	D) 2.5 kmph	E) 3.5 kmph
Rate upstream = (1/30 *60)= 
<gadget id="calculator">(1/30 *60)</gadget>
<output>2</output>
2 kmph   Rate down stream= 1/12 * 60= 
<gadget id="calculator">1/12 * 60</gadget>
<output>5</output>
5 kmph   Rate of the current= ½ (5-2) = 1.5 kmph   1.5 kmphNSWER:1.5 kmph
<result>A</result>
A boat moves upstream at the rate of 1 km in 30 minutes and down stream 1 km in 12 minutes. Then the speed of the current is :