Math Flashcards
Addition of Fractions:
Step 1: Make sure the denominators are the same. If not, get their least common denominator
ex: 1/3 +1/6. Their LCD is 6 because you can divide 6 by 3 (=2) and 6 by 6 (=1)
Step 2: Add the numerators, put the answer over the denominator.
ex: 1/3+1/6 = (2+1)/6 = 3/6
Step 3: Simplify the fraction (if needed)
3/6 is equals to 1/2
Answer this:
1/3 + 1/5 = ?
8/15
The exponent of a number says how many times to use the number in a multiplication.
In 8 raised to 2 (8^2) the “2” says to use 8 twice in a multiplication,
so 8^2 = 8 × 8 = 64
Answer this:
5^3 = ?
125
Subtracting a Negative is the same as Adding
Example: What is 6 − (−3) ?
6−(−3) = 6 + 3 = 9
now, answer this:
What is 14 − (−4) ?
18
Getting the percentage of a number Ex: What is 20% of 105? 1. Multiply 20 by 105. 20 x 105 = 2,100 2. Divide the answer by 100 2,100 /100 = 21
Now do this
Get the 51% of 66
33.66
Order of operation
Follow the following sequence in performing operations
MDAS = Multiplication, Division, Addition & Subtraction
Always do multiplication and division before addition and subtraction
Ex: 4+ 10 / 2 = 9 because 4 + (10/2) = 4+5=9
Ex: 16 / 2 x 4 = 2 bec. 16/(2x4) = 16/8=2
Answer this:
12 ÷ 6 × 2 = ?
1
In adding fractions with different denominators, how would you make the denominators equal?
By getting their Least Common Denominator .
Converting Improper Fractions to Mixed Fractions
1. Divide the numerator by the denominator.
2. Write down the whole number answer
3. Then write down any remainder above the denominator.
Ex: 11/4»_space; 11 ÷ 4 = 2 with a remainder of 3
Write down the 2 and then write down the remainder (3) above the denominator (4), like this: 2 and 3/4
Now answer this: convert 9/4 to mixed numner
2 and 1/4
Says how many times to use the number in a multiplication.
Exponent
(-) + (-) = ?
(-6)+(-6) = ?
(-)
-12
(-)+(+) = ? (-6)+(4) = ?
-2
Follow the negative sign because 6 (negative) is greater than 4 (positive)
(-6)+(10) = ?
4
Follow the positive sign because 10 (positive) is greater than 6 (negative)
(-) - (-) =?
(-4) - (-8) = ?
4
Remember, (-) + (-) = +
so - (-8) = +8
What does PEMDAS mean?
Parenthesis, Exponent, Multiplication, Division, Addition, Subtraction
Perform the operation
30 - 4^2 x 2 /2 =?
14 Why? Because 1. 4^2 = 16 2. 16 x 2 = 32 3. 32/2 = 16 4. 30 - 16 = 14
Perform the operation
5 + (3 x 3) / 4 - 5^2 x 3 =
- 3 x 3 = 9 so 5 + (9) / 4 - 5^2 x 3
- 5^2 = 25 so 5 + (9) / 4 - 25 x 3
- 25 x 3 = 75 so 5 + (9) / 4 - 75
- 9/4 = 2.25 so 5 + 2.25 - 75
- 5 + 2.25 = 7.25 so 7.25 - 75
- 7.25 - 75 = -67.75 so the answer is -67.75
