How do i memorize a passage in my Texas history book?

Well, you could start reading a sentence, and close your eyes and repeat the sentence. If you don't remember, open your eyes, take a peek, and start the sentence over. After you sucessfully mastered that part, you start by reading the next sentence. Then read the first sentence ALONG with the second sentence.

That's how I would do it.

part a. there were 250 teenagers surveyed (100% of tenagers = 250)therefore 1 % = 250/100 = 2.5 76% = 1% x 76 = 2.5 x 76 = 190 teenagers of the 250 surveyed liked burgerspart b: jane surveyed 25% (which is equal to 50 teenagers, i.e. a quarter of the teenagers surveyed is 50) to get 100% we simply get 4 quarters, i.e. multiply 50 by 4 = 200 teenagers were surveyed by jane. part c: it is impossible to give an example where a percentage is greater than 100%, since, by definition , percentage means "per 100".