Today, in Mathematics we are making study notes of Number for our topic test on Friday. Now, I go to Mathematics site and we are talking about Number, Order of Operation, Rounding, Standard Form, Percentage "of mean times", Percentage increase/decrease,
Number
- Multiples - Multiples are set of numbers that correspond to a base number that has been mulitplied by other numbers. A Multiple is formed by multiplying a given number by the counting numbers.
Multiples: 3, 6, 9, 12...
- Factor - Factor is a number or algebraic expression that divides another number or expression evenly. Factors are the numbers you mulitply together to get a product.
Factor: 15 - 1, 3, 5, 15
- Prime Number - A Prime Number are numbers that have only 2 factors. A Prime Number is a number that can only be divided evenly (no remainders) by itself and the number 1.
- HCF (Highest Common Factor) - Highest Common Factor is found by finding all common factors of two numbers and selecting the largest one.
Highest Common Factor is 4.
8: 1, 2, 4, 8
12: 1, 2, 4, 6, 12
- LCM (Lowest Common Factor) - Lowest Common Factor is a multiple number you get when you multiply a number by a whole number.
Lowest Common Factor is 24
6: 6, 12, 18, 24, 30, 36 ...
8: 8, 16, 24, 32, 40 ...
Order of Operation
Here is what we did to solve problems and it's called BEDMAS:
- B - stands for brackets.
- E - stands for exponents.
- D - stands for division.
- M - stands for multiplication.
- A - stands for addition.
- S - stands for subtraction.
Rounding
Rounding means replacing a number with an approximate value that has a shorter, simpler, or more explicit representation.
Example:
Replacing $23.4476 with $23.45, the fraction 312/937 with 1/3 or the expression √2 with 1.414.
Standard Form
Standard form allows us to write numbers without using as many digits. A number is standard form is written in two parts: Number from 1 to 9 x power of 10
Example:
35 946 (first number must be from 1 - 9)
followed by power of 10
Answer: 3.5946 x 10 power of 4
Percentage (of mean times)
In mathematics, a percentage is a number or ratio expressed as a fraction of 100.
3/5 of 400 = 240
10% of 600 = 60
Increase/Decrease:
To Increase/Decrease an amount by a percentage, first calculate the percentage of the amount and then either add this answer on to increase the quantity, or subtract this answer to decrease the quantity.
Example:
