Here’s today’s SAT question of the day:

The population of Norson, the largest city in Transitania, is 50 percent of the rest of the population of Transitania. The population of Norson is what percent of the entire population of Transitania?

Don’t jump to conclusions and say 50%  – let’s think (briefly) first so we arrive at the correct answer. The key phrase to focus on is “50 percent of the rest of the population“.  One is 50 percent of two, for example, but in this case 2 wouldn’t be the total population – it would be the rest of the population. To get the total population, we must add Norson’s population (in our example, 1) to the rest of the population (2); 1 + 2 =3, in case you weren’t sure.

Last step: what part is Norson of the total? 1/3, or .333333, or 33.333%…choice D.

Make sure you are comparing a part to the whole when you are working with percents – and if you don’t have the whole, see if you can find all the parts and add them up to make it!