**MACHINE SHOP CALCULATION - OD1640 - LESSON 1/TASK 1**

EXAMPLE 1.

Add 128 to 475.

Step 1.

Add the digits in the ones position.

5 + 8 = 13. Write 3 under the ones

position. Carry over the 1 to the

tens column.

Step 2.

Add the digits in the tens position.

1 + 7 + 2 = 10. Write the 0 under the

tens position. The 1 is carried

over to the hundreds position.

Step 3.

Add the digits in the hundreds

position. 1 + 4 + 1 = 6.

Step 4.

Check by adding from the bottom up following the procedure stated

in steps 1 through 3.

c.

*Subtraction*.

A requirement for subtraction is indicated by the

symbol -. The answer to subtraction problems is called the difference. To

find the difference between two numbers, write the numbers in columns under

each other, as in addition, and proceed as shown in Example 2.

EXAMPLE 2.

Subtract 25 from 78.

Step 1.

Subtract the digits in the ones

position. 8 - 5 = 3.

Step 2.

Subtract the digits in the tens

position. 7 - 2 = 5.

**3**