Indicate which of the following are exact numbers. (select all that apply.) 1.the number of microseconds in a week 2.the number of inches in a mile 3.the mass of a paper clip 4.the number of pages in a book 5.the surface area of a dime 6.the number of ounces in a pound

Exact numbers need not be measured. They can be counted. Conversion factors and countable units come under exact numbers. Measured quantities are measured using a device.

1) Number of microseconds in a week -Exact as it need not be measured. It can be estimated using the conversion factors between microseconds, seconds, minutes, hours, days and week.

2) Number of inches in a mile - Exact number as it is an established conversion factor.

3) The mass of a paper clip - Measured number as it has to measured using a weighing balance.

4) The number of pages in a book - Exact number as it is not measured. It can be counted.

5) Surface area of the dime-Measured number as it has to be measured.

6) The number of ounces in a pound-Exact number as it is a constant value.