A and B ran a race of 480 m. In the first heat, A gives B a head start of 48 m and beats him by 1/10th of a minute. In the second heat, A gives B a head start of 144 m and is beaten by 1/30th of a minute. What is B’s speed in m/s?
OA 12
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kaulnikhil
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let a and b take x and y sec respt to run the race of 480 mts
therefore
x + 6 = (432/480)*y
and
x = (336/480)*y +2
solve for y u get y = 40 sec
speed of b = 480/10 = 12
therefore
x + 6 = (432/480)*y
and
x = (336/480)*y +2
solve for y u get y = 40 sec
speed of b = 480/10 = 12
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tohellandback
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its your second line:xilef wrote:Where am I going wrong here?
t=d/s
432/SB - 480/SA = 6
336/SB - 480/SA = 2
Solve for SB:
SB=24m/s
SA=40m/s
336/SB - 480/SA = 2
it should be
480/SA-336/SB =2.
The powers of two are bloody impolite!!
