Numbers Operations CRCT review Real Numbers n All
Numbers & Operations CRCT review
Real Numbers n All rational and irrational numbers – all numbers that can be expressed as a decimal Rational Numbers *natural numbers *whole numbers *integers Irrational Numbers
Natural Numbers n aka counting numbers n ex: 1, 2, 3, 4, …
Whole Numbers n The natural numbers and zero n ex: 0, 1, 2, 3, 4, …
Integers n The set of whole numbers and their opposites n ex: …-4, -3, -2, -1, 0, 1, 2, 3, 4…
Rational Numbers n A number that can be written as a/b, where a and b are integers and b doesn’t equal 0. n includes fractions, repeating/terminating decimals n ex: -1/4, 6/5, . 0324, -3. 272727
Irrational Numbers n non-terminating and non-repeating decimals n Can’t be written as a/b n ex: 2. 34567…, n All numbers that are not rational are irrational
Rational or Irrational? 1. -7. 2 2. 1. 004 3. rational 4. rational 5. irrational
Absolute Value n The distance a number is from 0 =8 =0 =4 = -10
Comparing/Ordering Rational Numbers n Write all numbers in the same form (all decimals, all fractions, or all percents) EX. Order the numbers from greatest to least
Adding Signed (+/-) numbers 1. When numbers being added have the same sign, add the numbers and write the sign with the answer EX. 15 + 7 = 22 (-15) + (-7) = -22 2. When numbers being added have different signs: -subtract the absolute values of the numbers -use the sign of the number with the higher absolute value. EX. -15 + 7 = -8 (-7) + 15 = 8
Subtracting Signed numbers n Add the opposite Ex. -15 – 7 = -22
Multiplying/Dividing signed numbers n If there an even number of (-), then the answer is (+) EX. (-2)(3)(-4) = 24 n If there an odd number of (-), then the answer is (-) EX. (-2)(-3)(-4) = -24
Adding/Subtracting Fractions n Must have a common denominator 3 12 10 12
Multiplying fractions n Must write as improper fraction n Multiply the numerators n Multiply the denominators
Dividing Fractions n Write as improper fractions n “When you have 2 fractions and you want to divide, flip the second fraction and multiply. ”
Adding/Subtracting Decimals n Line up the decimals n Add/subtract as normal n Write the decimal point in the answer
Multiplying Decimals n Multiply as normal (ignore the decimals) n Count how many spaces over you need to place the decimal point in the answer
Dividing Decimals n If the divisor (outside the house) has a decimal point in it, then you have to move the decimal to the end. n Move the decimal point in the dividend (inside the house) the same number of places.
- Slides: 19