The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 km in 4 hours, then the speed of the first train is:
A.
B.
C.
D.
Answer: Option D
Explanation:	Choose the correct choice from the following
A) 70 km/hr	B) 75 km/hr	C) 87.5 km/hr	D) 84 km/hr	E) 75.6 km/hr
Let the speed of two trains be 7x and 8x km/hr.   Then, 8x =	400/4= 
<gadget id="calculator">400/4</gadget>
<output>100</output>
100   x=	100/8= 
<gadget id="calculator">100/8</gadget>
<output>25/2 = around 12.5</output>
12.5   8 Speed of first train= (7 x 12.5) km/hr = 87.5 km/hr.   answer :87.5 km/hr
<result>C</result>
The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 km in 4 hours, then the speed of the first train is:
A.
B.
C.
D.
Answer: Option D
Explanation: