# 1718 WB1Z CH10 Lesson 5

Which exercises/theory should I discuss on the board?
1 / 12
Slide 1: Woordweb
WiskundeMiddelbare schoolvwoLeerjaar 1

In deze les zitten 12 slides, met interactieve quizzen en tekstslides.

Lesduur is: 50 min

## Onderdelen in deze les

Which exercises/theory should I discuss on the board?

#### Slide 1 -Woordweb

Rounding up or down?
The formula                                       is given.
Take                          and solve the corresponding equation, round your answer to a whole number.

#### Slide 2 -Tekstslide

What is the rounded (to a whole number) solution to the equation
4c + 8 = 21?
A
3
B
4
C
5
D
6

#### Slide 3 -Quizvraag

Rounding up or down?
The formula                                       is given.
Take                          and solve the corresponding equation, round your answer to a whole number.

#### Slide 4 -Tekstslide

Rounding up or down?
In the formula
c stands for number of cars and n stands for number of athletes. The formula is about an athletics team that has a small bus that can take 8 athletes to an activity and also has several cars that can take 4 athletes to the activity.
21 athletes need to go to an activity, how many cars are needed?

#### Slide 5 -Tekstslide

How many cars are needed?
A
3
B
4
C
5
D
6

#### Slide 6 -Quizvraag

Rounding up or down?

3 cars will not be enough
So the answer is 4 cars. We ignore the normal rules for rounding off, because they don't work for this situation.

#### Slide 7 -Tekstslide

Rounding up or down?
If an exercise is about a realistic situation, you have to decide if you should follow the normal rules for rounding off or not.

#### Slide 8 -Tekstslide

Exact or an approximation
Some solutions to an equation are a fraction that cannot be written as a decimal number.
Example:

#### Slide 9 -Tekstslide

Exact or an approximation

The solution                      is called the exact solution
The solution                      is an approximation, accurate to two decimal places.

#### Slide 10 -Tekstslide

What is the EXACT solution to the equation 14a + 5 = 9
A
a=4
B
a=0.29
C
a=3.5
D
a=72

#### Slide 11 -Quizvraag

Homework Friday
Make and correct the exercises from the studyplanner up to and including §10.5: 30, 31, 32, 33, 34, 35