Explanation:

An estimate is an answer to a problem that is close to the solution, but not necessarily exact. Estimating can come in handy in a variety of situations, such as buying a computer. You may have to purchase numerous devices: a computer tower and keyboard for $1,295, a monitor for $679, the printer for $486, the warranty for $196, and software for $374. Estimating can help you know about how much you’ll spend WITHOUT actually adding those numbers exactly.

Estimation usually requires rounding. When you round a number, you find a new number that’s close to the original one. A rounded number USES zeros for some of the place values. If you round to the nearest TEN, you will have a zero in the ones place. If you round to the nearest hundred, you will have zeros in the ones and tens places. Because these place values are zero, adding or subtracting is easier, so you can find an estimate to an exact answer quickly.

It is often helpful to estimate answers before calculating them. Then if your answer is not close to your estimate, you know something in your problem-solving PROCESS is wrong.