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Grade 7 Midyear Exam. Memory Aid 2014. Prime and Composite Numbers. Prime number has only 2 divisors: E.g. 17 has 1 and 17. Composite number has more than 2 divisors: E.g. 24 has 1,2,3,4,6,8,12,24
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Grade 7 Midyear Exam Memory Aid 2014
Prime and Composite Numbers • Prime number has only 2 divisors: E.g. 17 has 1 and 17. • Composite number has more than 2 divisors: • E.g. 24 has 1,2,3,4,6,8,12,24 • Factorization: the number written as a product of factors. E.g. 24 written as 2 x 12 or 3 x 8 • Prime factorization: the number written as a product of its prime factors. E.g. 24 = 2 x 2 x 2 x 3 or 23 x 3
Order of Operations (bedmas) • 1. brackets • 2. exponents • 3. multiplication • 4. division • 5. addition • 6. subtraction • 3 and 4 can switch, 5 and 6 can switch
rounding • Example: 875.2763 • Round to the nearest hundred: 900 • Round to the nearest ten: 880 • Round to the nearest one: 875 • Round to the nearest tenth: 875.3 • Round to the nearest hundredth: 875.28 • Round to the nearest thousandth 875.276 • Look at the number to its right, if 5 or more add one and everything becomes zero after it, if 4 or less don’t change the number.
Exponents, square root • 45 = 4 x 4 x 4 x 4 x 4 • 40 = 1 • 41 = 4 • (-3)2 = -3 x -3 = +9 • (-3)3 = -3 x -3 x -3 = -27 • √16 = 4 because 4 x 4 = 16 (opposite of exponent 2)
Point, line, segment, ray • Angle bisector
Factor Trees for gcfanf lcm GCF = 2 x 3 = 6 LCM = 2 x 2 x 2 x 2 x 3 x 7 = 336
Graphs • 2 types of variables: qualitative (flavor or color) and quantitative (height, age) • Range = highest number – lowest number • Mean = average (add all the numbers and divide by the number of items) • Median = middle number in a list when the numbers are in order • Mode = the number that occurs most often • E.g. = 1,3,6,2,5,8 • range = 8-1 = 7 • mean = (1+3+6+2+5+8)/6 = 25/6 • median = 1,2,3,5,6,8 = (3+5)/2 = 4 • mode = none
Average • Sum of all the values divided by the total number of values.
Integers IF YOU ARE NOT SURE = USE YOUR CALCULATOR • Sum of 2 positive integers is positive • Sum of 2 negative integers is negative Subtracting Integers • -12 -5 = -12 + -5 = -17 • 26 - -14 = 26 + 14 = 40 Multiplication and Division • + x + or + ÷ + positive - x + or -÷ + negative • - x – or -÷ - positive + x – or +÷ - negative
Angle types and measures Zero angle
Opposite and adjacent angles • Opposite (1 = 3 or 2 = 4) Adjacent Same vertex, common side, not overlapping
Complementary and supplementary angles • Complementary: add up to 90 degrees and form a right angle. • Supplementary: add up to 180 degrees and form a straight line.
Alternate interior, exterior and corresponding angles • Alt int, alt ext and corresponding angles are congruent or equal when 2 parallel lines intersect a transversal line.
Parallel, perpendicular, intersecting and perpendicular bisector
Translation and reflection • Reflect by doing perpendicular lines with a triangular ruler on the reflection line. • Translate by doing parallel lines to the vector (prolong vector first) with a triangle on the vector and a ruler against the triangle.