Saturday PSAT General Discussion

basicspace
Sat, 20 Oct 2012 15:54:29 +0000

If I recall correctly, it was 20mi in 60mph and 8mi in 40mph.

You find the time with D=RT, so:
20=60T
8=40T
T=1/3hr
T=1/5hr

That gives you a combined time of 8/15 hours for 28 miles.
(8/15)R=28
R=52.5

Figured it out during the second math section with the extra time I had left :D.

Scared about the abs value one. The coefficient in the second one was -2 vs -4 in the first, so it would make sense that you would have to double the equation in the absolute value signs, making 4, but I doubt it would be as intuitive as that. I was just about to put 2 but decided against it.