Read the following text:
The pweor of the hmuan mnid.
Aoccdrnig to a rscheearch at Cmabridge Uinervtisy, it deosn’t mttaer in what oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a total mses and you can sitll raed it wouhit prbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.
First you might think: Hey, what the heck ... But after a few moments you get on with the text, and somehow it makes sense.
And here is the message of this story:
80% of the relevant information is at the beginning and at the end.
So if you are stuck for time, and there is a paragraph to read, then only read the first and last sentence of that paragraph. 80% of information is in those two sentences. (I know it sounds facetious, however try it out.)
If you are even more pressed for time, then read only the first and the last paragraph of a chapter. 80% of relevant information is in those two paragraphs.
Have a guess what comes next? If you are really, really stuck for time, and you have a book to read, then only read the first and the last chapter. Yes, here as well: 80% of the information you need for your exam is in those two chapters.
The question that really arises here is: Are you ok with a 80% result in your exam?