1Tvwo Ch 10 §10-4 The calculator

What is the main purpose of using the CALCULATOR ?


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Slide 1: Woordweb
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In deze les zitten 34 slides, met interactieve quizzen, tekstslides en 1 video.

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What is the main purpose of using the CALCULATOR ?


Slide 1 - Woordweb

Task 1:
John orders Chips and Cola for himself and 6 friends.
Prices: Chips € 2 and Cola € 1.65
How to calculate the total cost?
A
cost = 2 + 1.65 x 7
B
(2 + 1.65) x 7 = cost
C
7 x (2 +1.65) = cost
D
cost = (7 + 1.65) x 2

Slide 2 - Quizvraag

Explanation Task 1:

Both prices, 2 € and 1.65 €, have to be multiplied by 7, because all the 7 boys get Cola and Chips.
This is done by putting brackets over 2 + 1.65

Slide 3 - Tekstslide

Task 2:
Calculate, using your calculator:
a. 13.5 + 9.2 x 8.3 =
A
89.68
B
89.86
C
98.86
D
98.68

Slide 4 - Quizvraag

Task 3:
Calculate, using your calculator.
6.1 x (3.7 - 5.4) =
A
13.07
B
10,37
C
-10.37
D
-13.07

Slide 5 - Quizvraag

Task 4:
6.5 x 8.2 + 4.8 : 8 =
A
35,9
B
95.3
C
39,5
D
53.9

Slide 6 - Quizvraag

Comment on Task 2, 3 and 4
Calculating these exercises asks precision from you.
Not forgetting anything, for example brackets!
The funny thing is, you do not have to really understand anything about 'order of operations' for this task.
Your sillicone friend, the calculator, takes good care of that!

Slide 7 - Tekstslide

Slide 8 - Video

Task 5:
Write as decimal numbers, using your calculator.
Round to 3 decimal numbers.

4228
A
0.667
B
0,667
C
0.666
D
0,666

Slide 9 - Quizvraag

Explanation task 5:

 To write          as a decimal number, rounding to 3 decimal numbers,
you  can do:    
 - key in:  '28 : 42 =' , followed by rounding,        
or: use the 'a  b/c' button, left column, 3rd from above:
     - key in:  '28  a  b/c  42 ='. Now you get your answer as a fraction!
To change this into a decimal number, key in:  a  b/c.
Finally round again.
4228

Slide 10 - Tekstslide

Task 6:
Do the same with:
6
97
A
7.668
B
6.887
C
6.778
D
8.667

Slide 11 - Quizvraag

Explanation Task 6:
How to key in:    6       ?
Two ways:
               -        6 + 7 : 9 =        , or:
               -         6  a b/c   7  a b/c  9  =
Now you get the answer as a fraction. To change this to a decimal number, key in: a  b/c.
Finally round your answer to 3 decimal places.

97

Slide 12 - Tekstslide

Task 7:
Do the same with:
39
5147
A
93.922
B
39,922
C
92.229
D
39.922

Slide 13 - Quizvraag

Task 8:
Calculate and round to whole numbers:

8842 x
135
A
3400
B
3401
C
340.1
D
34.1

Slide 14 - Quizvraag

Instruction A :
How to solve an equation and round the answer?
Example:
Solve this equation:
47c - 38 = -7 (place a card on 47c)
47c = 31
c = 
 c        0.660 
For this notation, see next slide! 
4731

Slide 15 - Tekstslide

N  Notation of an approximation:
Instruction B:
The solution 
is written as a decimal number as follows:                    0.660
This number is rounded to 3 decimal places. 
The symbol         means 'is approximately equal to' and indicates that it is a rounded number.
4731
4731

Slide 16 - Tekstslide

Task 9:
Solve and round the following equation on paper:
17 + 16x = 40
Round your answer to 3 decimal places.
Finally choose the right answer!
A
1.44
B
1.438
C
1,44
D
14.4

Slide 17 - Quizvraag

Explanation task 9:
Solve this equation:
17 + 16 x = 40
16 x = 23 
x =  
Rounded to three decimal places  x      1.438
1623

Slide 18 - Tekstslide

Task 10:
Solve the following equation on paper:
-9v + 19 = 32
Round your answer to three decimal places.
Use this sign, which means 'is approximately equal to':
Finally choose the right answer!

A
1.44
B
-1.444
C
-1.445
D
1,444

Slide 19 - Quizvraag

Explanation Task 10:
a. -9v + 19 =32
-9v = 13
v = 
v      -1.444
913

Slide 20 - Tekstslide

HOMEWORK
From now on, some homework exercises appear.
If you keyed in the wrong answer, try again!
You have the choice between:
- doing extra basic exercises (purple circle), for the BLUE group (needing more help)
- doing more challenging exercises (yellow circle), for the GREEN and PURPLE group
  (ready for more complicated exercises)
- doing both types of exercises (purple and yellow circles),          
   but remember: do at least half of all exercises!
   Maybe you even do all of them.


Slide 21 - Tekstslide

Extra BASIC:
Task 11:
Calculate, using your calculator:
0.5 + (4.6 + 12.4 ) : 34 =
A
2
B
1
C
0
D
3

Slide 22 - Quizvraag

Etra Basic:
Task 12:
Calculate:
(24.9 - 12.5) x 8.8 - 10.4 =
A
89.72
B
98,72
C
98.72
D
97.72

Slide 23 - Quizvraag

Task 13:
Which numbers(s) cannot be written as a decimal number that has exactly the same meaning?

41
32
65
54
A
2/3 only
B
1/4 and 5/6
C
5/6 and 4/5
D
2/3 and 5/6

Slide 24 - Quizvraag

Task 14: Extra Basic: Calculate and round to 2 decimal places:
477 x
74
A
272,57
B
227.57
C
272.57
D
227.571

Slide 25 - Quizvraag

Task 15:
Solve this equation on paper.
Use the card method.
Round your answer to 3 decimal places.
Finally choose the right answer.

47c - 38 = -7
A
0.660
B
0.661
C
0.659
D
0,660

Slide 26 - Quizvraag

CHALLENGE:
Task 16:
Make an equation for the following information:

27 Players of a football club will be taken to their match.
5 Of them always travel with their coach in his car.
There is room for 3 players in each of the cars of the parents.
Call the number of parents n.
Which of the following equations is correct?
A
27 = 4n + 5
B
5n + 3 = 27
C
5 + 3n = 27
D
27 = 5n + 3

Slide 27 - Quizvraag

CHALLENGE:
Task 17:
Solve the equation from the previous slide:
5 + 3n = 27
So: calculate n, the number of parents.
This number has to be rounded sensibly!
A
n = 7.333
B
n = 7
C
n = 7 .3
D
n = 8

Slide 28 - Quizvraag

Extra Basic
Task 18:
Solve this equation on paper.
Round your answer to 3 decimal places.
Finally choose the right answer.
2388 = 2000x + 387
A
1.0005
B
1,002
C
1.001
D
-1.001

Slide 29 - Quizvraag

Extra Basic:
Task 19:
Solve this equation on paper.
Finally key in the answer, rounded to 3 decimal places:
123 = 23e - 3

A
5.47
B
5.48
C
5,48
D
5.478

Slide 30 - Quizvraag

Dear boys and girls, this was the final 'extra exercise'.
There is one more 'challenge exercise' to come. 
Hope you learned a lot and enjoyd too!

Slide 31 - Tekstslide

CHALLENGE:
Task 20:
In 2008 a world record was set for the fastest journey around the world in a speed boat. It lasted 1663.82 hours.
Calculate this in days, hours and minutes. Round to whole minutes.
A
99,829.2 minutes
B
69 days, 7 hours and 49 minutes
C
69 days, 7 hours and 53 minutes
D
69 days, 7 hours and 54 minutes

Slide 32 - Quizvraag

Dear boys and girls, the task you've just been doing was the final homework exercise!
Hope you learned a lot and enjoyed!

Slide 33 - Tekstslide

Homework time
Do §10-4 The calculator now,
afterwards checking your results with the
Solutionbook.

Slide 34 - Tekstslide