In the clinical laboratory, elementary mathematics are frequently used by the

laboratory specialist to calculate the amount of a specific chemical needed to prepare a

reagent or to determine the concentration of a chemical constituent in a clinical sample.

To enable the laboratory specialist to perform calculations with greater efficiency, the

use of scientific notation must be mastered.

An exponent is a superscript number written to the right of a base number. An

exponent indicates the number of times the base number is to be used as a

multiplicative factor to produce a product equal to the exponential expression.

a. **General Examples**.

(1)

32 = 3 X 3 = 9

In the above example, the exponent is the number two and indicates that the number

three, referred to as the base number, is to be used as a multiplicative factor twice.

(2)

23 = 2 X 2 X 2 = 8

In the above example, the exponent is the number three and indicates that the base

number two is to be used as a multiplicative factor three times.

b. **Examples Using Powers of Ten (10)**.

(1)

102 = 10 X 10 = 100

(2)

103 = 10 X 10 X 10 = 1000

The following rules apply to exponential expressions that have the same base

with the exception of addition and subtraction.

a. **Addition and Subtraction**. The expressions must first be evaluated. Then,

addition or subtraction is performed in the usual manner.

Example.

102 + 101 = 100 + 10 = 110

MD0837

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