Study Guide Questions
Posted: Mon Dec 31, 2012 1:11 amThere are a couple of study guide problems I'm having trouble with. Here they are:
12B-37. Bulk potatoes are sliced into 0.02 in thick slices to make potato chips.
A potato loses 75% of its mass during frying. Potatoes on average are 6 in long,
weigh 0.8 lb and cost $0.88/lb. An 11-oz bag of chips costs $2.58 and has 128
chips. What is the ratio of the cost of chips to the cost of the starting bulk
potatoes needed to make those chips (on a mass basis)?
This one is just confusing. I have no idea what to do.
10I-37. What is the minimum elevation above the earth’s surface necessary to
have a direct line of sight to both Fiji and New Zealand if they are 1314 mi
apart? Neglect refraction.
This one, I figured out a solution a couple of different ways. However, both give me an answer that's a couple percentage points off. The radius of the Earth is 3960 miles (or at least, that's what has been used on this test in the past.) I derived a couple of formulas for this problem, and back-calculated the radius of the Earth using their given value and my formulas; I arrived at a radius of about 3998 (3996? Somewhere around there) miles for the Earth. This could just be a rounding error in the solution, and meaning that the problem writer actually decided to use 4000 miles flat.
Anyone have any ideas for these two?
Also, are there better solutions for a few of the geometry problems than just pure Law of Cosines and Law of Sines, over and over again?
12B-37. Bulk potatoes are sliced into 0.02 in thick slices to make potato chips.
A potato loses 75% of its mass during frying. Potatoes on average are 6 in long,
weigh 0.8 lb and cost $0.88/lb. An 11-oz bag of chips costs $2.58 and has 128
chips. What is the ratio of the cost of chips to the cost of the starting bulk
potatoes needed to make those chips (on a mass basis)?
This one is just confusing. I have no idea what to do.
10I-37. What is the minimum elevation above the earth’s surface necessary to
have a direct line of sight to both Fiji and New Zealand if they are 1314 mi
apart? Neglect refraction.
This one, I figured out a solution a couple of different ways. However, both give me an answer that's a couple percentage points off. The radius of the Earth is 3960 miles (or at least, that's what has been used on this test in the past.) I derived a couple of formulas for this problem, and back-calculated the radius of the Earth using their given value and my formulas; I arrived at a radius of about 3998 (3996? Somewhere around there) miles for the Earth. This could just be a rounding error in the solution, and meaning that the problem writer actually decided to use 4000 miles flat.
Anyone have any ideas for these two?
Also, are there better solutions for a few of the geometry problems than just pure Law of Cosines and Law of Sines, over and over again?