Tutor profile: Paul M.
What is the best test taking strategy for SAT and PSAT test takers when they aren't sure what the correct answer is?
Any multiple choice test can be broken down by first eliminating any clearly wrong answers. If two answers can be eliminated, suddenly a pure guess between remaining answers is 50/50. After careful consideration (a few minutes), if you have NO idea which of the 4 answers is correct, there is some value in skipping a question. Each correct answer is worth 1 point toward your final score. Each wrong answer deducts .25 points. Skipping a question when you have a low chance of guessing the correct answer can help your final score.
What is the difference between a mean, median, and mode? What is the mean, median, and mode for the following number group (11, 16, 22, 13, 11)? Name one real-world scenario where each is used.
Mean - The mean is the average. Add up the values and divide by the number of values. 11 + 16 + 22 + 13 + 11 = 14.6 This would be useful if you were looking to determine the average number of students in the 3rd grade classrooms in a school district Median - Median means middle (Remember: the concrete barrier in the middle of the road is called a median). Line the values from smallest to largest and find the middle value. 11, 11, 13, 16, 22. The median is 13. (If you have an even number of values, the median is the average of the 2 middle numbers) The median can be useful for determining demographics for things like income. If you have a millionaire in a focus group of average workers, their salary will bloat the average, but the median will be more accurate for describing the group as a whole. Mode - the number that appears the most. 11 appears twice, so 11 would be the mode. (A number set can be multi-modal) Any election is a mode. The name (or value) that appears the most is a winner.
Lane wants to buy a game that costs $30 and a DVD that costs $10. He knows that there will be a sale in 2 weeks where his final total will be 20 percent off. He can make $10 per lawn he mows in his neighborhood. He currently has $7. How many lawns will he need to mow in the next two weeks to get both things that he wants?
The best way to work out the answer is to break it down piece by piece. 1) How much money does he need for the items? The total for the two items is $40, BUT the sale means he can get them for less. 20 percent off will save him 8 dollars (40 * .8 = 32). So he needs to have 32 dollars. 2) How much of that money does he need to make? 32 needed minus 7 dollars currently = 25 dollars, so he needs to make at least 25 dollars. 3) How many lawns does he need to mow to make $25? I would teach this by simple counting. 1 lawn = $10, 2 = $20, 3 = $30 (because you cant mow half a lawn, usually). Final answer: 3 lawns This is designed to be a practical application of algebra principals. After I take the student through the problem, I would then work backwards, replacing certain numbers with variables in the original problem. In my experience, the biggest problem with introducing algebra is that students have difficulty understanding that a letter has a numeric value. This method shows them the numeric value and then draws comparisons to the variable to help them change their thinking.
needs and Paul will reply soon.