Some SAT I Math Problems that I don't know how to solve.

fresh101
Fri, 27 Nov 2009 21:35:57 +0000

To find the average of the 20 miles, find the total time for each 10 mile ride. So, for the 10 miles driven with an average speed of 20 miles/hour, the time was 30 minutes and for the 10 miles driven with an average of speed of 40 miles/hour, the time was 15 minutes. Add the time together (45 minutes). So you know you rode 20 miles in 45 minutes or 80/3 miles per hour.
Compute all the multiples of 6 and 8 that are less than 50. So, for multiples of 6, they would be 6, 12, 18, 24, 30, 36, 42, and 48; multiples of 8 are 8, 16, 24, 32, 40, and 48. There’s only two common numbers (24 & 48)


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The answer is A because you can rewrite the inequality two ways: you can rewrite it the way it is and by taking away the sign and adding a negative. So, x-32<2 or x<34 is one way of rewriting it and the other way is x-32>-2 or x>30. Both these expressions fit the recommendation that the tire has to be less than 34 but greater than 30 psi.