1 / 13

Multiplying and dividing positive and negative numbers

Multiplying and dividing positive and negative numbers. Slideshow 5, Mr Richard Sasaki Room 307. Objectives. Multiplication and d ivision drill Learn rules for multiplying negative numbers Learn rules for dividing negative numbers Practice multiplying and dividing negative numbers.

valiant
Download Presentation

Multiplying and dividing positive and negative numbers

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Multiplying and dividing positive and negative numbers Slideshow 5, MrRichard Sasaki Room 307

  2. Objectives • Multiplication and division drill • Learn rules for multiplying negative numbers • Learn rules for dividing negative numbers • Practice multiplying and dividing negative numbers

  3. Multiplication and Division Drill You have four minutes to complete the drill, good luck!

  4. Answers 3 12 15 5 12 46 27 24 4 24 1 16 3 0 50 3 12 32 7 40 45 40 200 6½ 36 3 4 16 14 30

  5. Answers • And here is your rating… • 1 – 4 Terrible… • 5 – 8 Disaster… • 9 – 12 Poor… • 13 – 15 So-so… • 16 – 17 Okay • 18 – 19 Good • 20 - 21 Great! • 22 - 24 Fantastic!! • 25 - 26Super Excellent!! • 27 - 30 Unbelievable!!!!

  6. Multiplying with Negative Numbers Rules for multiplying negative numbers are similar to adding or subtracting. Example Numerically, Double -4 = (-4) – 4 = (-4) x 2 Double -4. Let’s look at the number line. x2 If we double -4, we double its “size”. As it’s negative it must go further to the left. We double -4 and come to -8. This is the same as -4 and taking away another 4.

  7. Multiplying with Negative Numbers Let’s try another example. Example Calculate (-5) x 4. So here we extend -5 four times and reach -20. (-5)x 4 = -20 Basically, if we multiply a negative number by a positive, we get a negative.

  8. Multiplying with Negative Numbers How about two negatives? Example Calculate (-5) x (-6). Here we increase the weight of -5, but it goes the opposite way as it’s by a negative amount. (-5)x (-6) = 30 When we multiply a negative number by another, the answer will be positive.

  9. Dividing Negative Numbers Dividing has exactly the same rules. Examples Calculate 10 ÷ (-5). 10÷ (-5) = -2 Calculate (-18) ÷ 6. (-18)÷ 6 = -3 It doesn’t make any difference which number in the calculation is negative. If one is negative, the answer will be negative.

  10. Dividing Negative Numbers Like multiplication, if we divide a negative number by another, our result is positive. Examples Try the worksheets! Calculate (-60) ÷ (-6). (-60)÷(-6) 10 = Calculate (-5) x 8 ÷ (-2) (-5)x 8 ÷ (-2) = (-40)÷(-2) = 20

  11. Answers - Easy -15 -3 -36 -3 -10 -5 25 -36 21 -4 -10 -90,000 Yen 72

  12. Answers - Medium -60 3 -2 -3 -4 -1 -6 -8 -4 -2 1 -3 -6 -9 -12 -121 -8 -16 -4 -12 -4 1 degrees 1 0.25

  13. Answers - Hard 8 -53m -24 108 -38m 12 2 16 -0.5 -64

More Related