1.1 Intro to Rational Numbers
A number that can be written as a fraction without the denominator being 0 is called a...
Rational Number
change 1/5 to a decimal
1/5 = 20/100= 0.2
change the following improper fraction to a mixed number:
9/4
9/4 = 2 1/4
Is 81 a perfect square?
Yes because the square root of 81 is 9
What is the correct order of operations?
Brackets
Exponents
Division/ Multiplication from left to right
Addition/ Subtraction from left to right
A decimal can be changed to what other types of rational numbers?
Fractions!
Percents!
1.5
Solve:
1/8 - 2/8 =
15.937
Is this correct?
5 + 3 x 2 = 16 ?
No.
5 + 3 x 2 = 11
What type of decimal is the following:
7.33333333...
Repeating decimal
Using estimation, would you expect the solution to be negative or positive?
-1.7 - (-0.3) =
estimate: -2 - (-0.5) = -2 + 0.5 = negative
Solve:
3/5 + 1/15
9/15 + 1/15 = 10/15 = 2/3
What is 112 ?
121
Solve:
-3.5 + (0.2 x 1.3) =
-3.24
If the number can not be written as a fraction, it is known as what?
Provide an example
Irrational number
pi, 7.84909283032...
calculate:
5.2 x (-3.1) =
-16.12
Solve:
Sally has $39, she gave 2/3 of this amount to her sister.
How much did Sally give?
2/3 x 39
2/3 x 39/1 = 78/3 = 26
Sally gave her sister $26
When you calculate the square of a number, are you solving for the area of a square or the side length?
Area
(cm2 , m2, units2)
Solve:
1/4 x 1/6 + (1/2 - 3/4)
-5/24
order the following rational numbers from lowest to highest:
-1, 0.5, -0.8. 0.56, 1.3
-1, -0.8, 0.5, 0.56, 1.3
Which decimal is larger?
1.3 or 1.3333...
1.3333...
Solve
6 1/2 divided by 2/3
13/2 x 3/2 = 39/4
= 9 3/4
If you did not have a calculator, what would you estimate the square root of 28 to be?
We know:
5 x 5 = 25
6 x 6 = 36
We might expect the square root of 28 to be in the range of 5.1-5.5
Solve:
3/4 + (0.5 x 3)
= 2.25
or 2 1/4