1_1c Evaluating Expressions with Units

Instructions

Example 1

Evaluate the expression (3m+5m)*4.
Write these steps: Think these reasons:
Write the given expression. (3m+5m)*4 The first step is to write the given expression. Now we start to evaluate the expression. First we check if all units are in SI notation. The unit cm is not SI. Therefore the next step is to convert cm to m.
Convert unit cm to m. = 8m*4 Next we evaluate the multiplication.
Multiply. = 32m Finally, we indicate that this is the answer.
Underline the answer.




Example 2

Evaluate the expression 30m-10ft/2.
Write these steps: Think these reasons:
Write the given expression. 30 m - 10 ft / 2 The first step is to write the given expression. Now we start to evaluate the expression. First we check if all units are in SI notation. The unit ft is not SI. Therefore the next step is to convert ft to m.
Convert unit ft to m. 30 m - 3.048 m / 2 Next we evaluate the division. Therefore the next operation is a unit conversion.
Divide. = 30 m - 1.524 m Next, evaluate the subtraction.
Subtract. = 28.476 m Finally, we indicate that this is the answer.
Underline the answer.




Example 3

Evaluate the expression .

Write these steps: Think these reasons:
Write the given expression. The first step is to write the given expression. Now we start to evaluate the expression. First we check if all units are in SI notation. The unit km is not SI. Therefore the next step is to convert km to m.
Convert unit km to m. We check again, if all units are in SI notation. The unit h is not SI. Therefore the next step is to convert h to s.
Convert unit h to s. The next step is a division.
Add. The next step is an addition.
Divide. Finally, we indicate that this is the answer.
Underline the answer.

Example 4

Evaluate the expression .

Write these steps: Think these reasons:
Write the given expression. The first step is to write the given expression. Now we start to evaluate the expression. First we check if all units are in SI notation. The unit cm is not SI. Therefore the next step is to convert cm to m.
Convert unit ft to m. Next, we check if all units are in SI notation. The unit cm is not SI. Therefore the next step is to convert cm to m.
Convert unit cm to m. The next step is an addition.
Add. Finally, we indicate that this is the answer.
Underline the answer.

Algebra Section 1_1
Exercises


Index