MATHEMATICS SECONDARY 1 NA THE FOUR OPERATIONS ON

MATHEMATICS SECONDARY 1 (NA) THE FOUR OPERATIONS ON INTEGERS

APPLES FOR SALE! You have 10 apples at the beginning of the day. You stock up 10 times the amount you have at the beginning of the day. Customer A asked to buy 7 apples. You have to divide the apples you have left equally between Customer B, C and D. If you were to write out the numerical expression, is it ……….

What is your answer ? (a) 10 x 10 – 7 3 (b) ((10 x 10) -7) 3 (c) both are the same

Summary • The order of operations in any numerical problem and word problem is important. It affects the final outcome.

Revision on Operations of Integers 3+3 = 6 3+2 = 5 REVISION: 3+1 = 4 3+0 = 3 +(-1) = - 1 3+(-1)= 2 +(-2) = - 2 3+(-2)= 1 3+(-3)= 0 3+(-4)= -1 GETTING THE HANG OF THE PATTERN? ? 3+(-10)= -7

Revision on Operations of Integers (i) 3 -3 = 0 REVISION: 3 -2 = 1 3 -1 = 2 -(-1) = +1 3 - 0= 3 -(-2) = +2 3 -(-1)= 4 3 -(-2)= 5 3 -(-10)= 13

Revision on Operations of Integers (ii) Click for the correct answer. Compare the difference in answers due a change in sign Q 1 : 3 + 1 = 4 Q 2 : 3 + 0 = 3 Q 3 : 3 + (-3) = 0 Q 4 : 3 + (-4) = -1 Q 5 : 3 + (-25) = -22 = 3 Q 7 : 3 - (-1) = 4 Q 8 : 3 - (-5) = 8 Q 9 : 3 - (-10) = 13 Q 10 : 3 - (-25) = 28 Q 6 : 3 - 0

WORKSHEET (1)Q 1 Refer to the slides for examples to proceed with your worksheet. Clue to Question 1: 2+ 5 +1 = 8 -2 -5 -1 = -8

Revision on Operations of Integers (iii) 3 3=1 3 2 = 1. 5 3 1=3 3 x 3=9 3 x 2=6 3 x 1=3 3 x 0=0 3 x (-1)= -3 3 x (-2)= -6 3 x (-3)= -9 3 0 = undefined 3 (-1)= -3 3 (-2)= -1. 5 3 (-3)= -1 What happens when you multiply/divide 2 numbers with the same sign? Look at the Pink Boxes.

Revision on Operations of Integers (iv) What happens when you multiply/divide 2 numbers with different sign? Look at the Blue Boxes. -3 3 = -1 -3 2 = -1. 5 -3 1 = -3 -3 0 = undefined -3 x 3 = -9 -3 (-1)= +3 -3 x 2 = -6 -3 (-2)= +1. 5 -3 x 1 = -3 -3 (-3)= +1 -3 x 0 = 0 -3 x (-1)= + 3 ( you can write ‘ 3’) -3 x (-2)= +6 -3 x (-3)= +9

Revision on Operations of Integers (v) 3 3=1 -3 3 = -1 3 2 = 1. 5 -3 2 = -1. 5 3 1=3 3 x 3=9 3 x 2=6 3 x 1=3 3 x 0=0 3 x (-1)= -3 3 x (-2)= -6 3 x (-3)= -9 -3 1 = -3 3 0 = undefined 3 (-1)= -3 3 (-2)= -1. 5 3 (-3)= -1 -3 0 = undefined -3 x 3 = -9 -3 (-1)= +3 -3 x 2 = -6 -3 (-2)= +1. 5 -3 x 1 = -3 -3 (-3)= +1 -3 x 0 = 0 -3 x (-1)= + 3 ( you can write ‘ 3’) -3 x (-2)= +6 -3 x (-3)= +9

Revision on Operations of Integers(vi) Look at the PINK and BLUE Boxes. Do you see a pattern? What happens when you multiply/divide 2 numbers with the same sign? Look at the Pink Boxes. What happens when you multiply/divide 2 numbers with different sign? Look at the Blue Boxes.