# Math problem D:

by Alex
(State)

When it is known, you can substitute a numerical value for the variable.

The numerical value and the variable can be interchanged when are equivalent.

My question is:

What is 8m for n = 8?

### Comments for Math problem D:

 Sep 08, 2011 Math problem D - Equivalence by: Staff The question: by Alex (State) My question is: What is 8m for n = 8? The answer: 8m for n = 8? I assume you actually mean m=8 (rather than n=8) You can calculate 8m by replacing the m with the number 8. m=8 8m = 8m = 8*8 = 64 The final answer is: 8m = 64 Why can you substitute the number 8 for the variable m? The m and the 8 can be interchanged is because they are equivalent. Other examples of equivalent values are: 4 quarters = \$1; 1 ton = 2000 pounds; 1 mile = 5,280 feet, ½ = 0.5. The list of equivalent values is endless. Equivalence is important because it makes substitution possible. If two items are equivalent, one item can be replaced with the other, or vice versa. Being able to substitute one value with another simplifies problem solving. Thanks for writing. Staff www.solving-math-problems.com