If the calculation was:
3+7-2*7/4
You may think this would be calculated as
3+7 -2 *7 /4
=
8 *7 /4
=
56/4
=
14
In fact it is calculated as
3+7 -2*7/4
=3+7 -14/4
=3+7 -3.5
= 1 0 -3 .5
=6.5
Prove this by typing in this calculation as it is written:
Type:
[ENTER]
?3+7 -2*7/4
6.5
You can change the way the computer calculates this by adding brackets. The computer will deal
with the calculation inside brackets prior to the multiplication etc, outside the brackets. Prove this
by typing in the calculation including brackets.
Type:
?(3+7-2)*7/4 [ENTER]
FURTHER EXPONENTS
If you want to use very large or very small numbers in calculations, it is sometimes useful to use
scientific notation. The letter E is used for the exponent of numbers to the base 10. You may use
either lower case e or upper case E.
For example 300 is the same as 3x10
as 3x10
). In scientific notation this is 3E-2. Try the following examples.
-2
1. 30x10
You can type in:
? 3 0 * 1 0 [ E N T E R ]
300
. In scientific notation, this is 3E2. Similarly, 0.03 is the same
2