1. Computation in Other Bases
4.4
Computation in Other Bases

2. Addition
An addition table can be made for any base and it can be used to add in that base.
Base 5 Addition Table 13 12 11 10 4 3 2 1 +

3. Example: Using the Base 5 Addition Table
+ 235
Solution:
From the table = 125.
Record the 2 and carry the 1.
1445
+ 235 25

5. Example: Using the Base 5 Addition Table continued
Add the numbers in the second column,
( ) + 25 = = 125.
Record the 12.
1445
+ 235
1225
The sum is 1225.

6. Subtraction Subtraction can also be performed in other bases.
When you “borrow” you borrow the amount of the base given in the subtraction problem.
Example: If you are subtracting in base 5, when you borrow, you borrow 5.

7. Multiplication
Multiplication table for the given base is extremely helpful.
Base 5 Multiplication Table 31 22 13 4 14 11 3 2 1 

8. Example: Using the Base 5 Multiplication Table
Multiply
 35
Solution:
Use the base 5 multiplication table to find the products. When the product consists of two digits, record the right digit and carry the left digit.

9. Example: Using the Base 5 Multiplication Table continued
Record the 1 carry the 1.
1125
 35 1
(35  15) + 15 = 45 Record the 4.
125
 35
The product is 415.

10. Division
Division is carried out much the same way as long division in base 10.
A division problem can be checked by multiplication.
(quotient  divisor) + remainder = dividend

12. Homework
P. 198 # 9 – 54 (x3)