Microsoft Office Tutorials and References

In Depth Information

**Using GCD and LCM to Perform Seventh-Grade Math**

Using

Using
GCD

GCD
and

and
LCM

LCM
to Perform Seventh-Grade Math

to Perform Seventh-Grade Math

My seventh-grade math teacher, Mr. Irwin, taught me about greatest common

denominators and least common multiples. For example, the least common

multiple of 24 and 36 is 72. The greatest common denominator of 24 and 36 is 12.

I have to admit that I never saw these concepts again until my son Josh was

in seventh grade. This must be permanently part of the seventh-grade cur-

riculum.

If you are in seventh grade or you are assisting a seventh grader with his or

her math lesson, you will be happy to know that Excel can calculate these

values for you.

Syntax

=GCD(number1,number2,...)

The GCD function returns the greatest common divisor of two or more integers.

The greatest common divisor is the largest integer that divides both number1

and number2without a remainder.

The arguments number1, number2,... are one to 255 values. If any value is

not an integer, it is truncated. If any argument is nonnumeric, GCD returns a

#VALUE! error. If any argument is less than zero, GCD returns a #NUM! er-

ror. The number 1 divides any value evenly. A prime number has only itself

and 1 as even divisors.

Syntax

=LCM(number1,number2,...)

The LCM function returns the least common multiple of integers. The least

common multiple is the smallest positive integer that is a multiple of all in-

teger arguments
—
number1, number2, and so on. You use LCM to add fractions

with different denominators.

The arguments number1,number2,...are one to 29 values for which you want

the least common multiple. If the value is not an integer, it is truncated. If

any argument is nonnumeric, LCM returns a #VALUE! error. If any argument is

less than 1, LCM returns a #NUM! error.