Review of Algebra/Intro to Calculator

NOTATION: 2/3 division (instead of 2÷3)

(2)(3) multiplication (instead of 2x3)

2 < 3 2 is less than 3

2 3 2 is less than or equal to 3

2 > 3 2 is greater than 3

2 3 2 is greater than or equal to 3

square root

| 15 | absolute value of 15 ( |-15| = + 15)

If there is an arithmetic statement within absolute value signs, remember to do arithmetic first, then take absolute value.

| 1-24 | = 23

k

i summation = the sum of all Xi where i goes from j to k.

j=1 (j usually starts at 1.)

= sigma

j = start

k = end

i = case

REVIEW

A. Fraction to decimal conversion

4/10 = .40 Take 4 and divide it by 10.

B. Signed numbers

1. addition--same sign: Add absolute values of numbers and give answer of common sign.

2. addition--unlike sign: Get difference between numbers and give answer in sign of larger number.

3. subtraction: Change sign of number to be subtracted, then proceed as if it were an addition problem.

4. multiplication and division: Like signs will yield a positive answer, unlike signs will yield a negative answer.

Examples:

+2-2-3 +4+4+3(+2) = 6
+3-3+2 -3+3-3(-2) = 6
+5-5-1 +1+7-3(+2) = -6

C. Solving a complex expression--guidelines:

1. Do the math within parenthesis first, beginning with most interior parenthesis.

2. Do exponents. (Do all the math under a square root before taking the square root).

3. Do all math in the numerator, then do the denominator, then divide (do not try to cancel).

4. Unless stated otherwise, students will be expected to minimally work as accurately as 1/1000th range and round their answers to the 1/100th or to two decimal points.

A complex expression:

= -1

parentheses

{ [ ( ) ] }braces

brackets

* In statistics always use the positive square root.

Practice with calculator:

This entire problem can be done without storing any data.

table of contents

homework

next lesson