Math?

Remember dont just type in the answer, in other words explain it clear so it can be comprehensible.

1.Erik works 35 hours under one week and earns 3010 SEK. Anna has the same hourly wage and earns 1892 SEK.

a) How many hours have Anna worked?

b) Type a formula that shows how Anna’s salary depends of how many hours she worked. Let
y
be the pay in SEK when she worked
x
hours.

2. When to take a driving license in (Roy and Rogers) driving school in Trollhattan, the theory and the mandatory driving lessons cost together 2300 SEK. The extra/additional driving lessons cost 220 SEK per lesson.

a) What will Lars pay total/altogether to the driving school if he also takes 12 extra/additional driving lessons?

b) Sara, who just recently accomplished to get the driving license, paid 4060 SEK to the driving school. How many extra/additional driving lessons did she take?

c) Write a formula that describes how much you will pay in total for the driving school if you undergo/experience a driving lesson and take
x
extra/additional driving lessons.

3. In a store they sell measure ordered carpets. The price for the carpet is 295 SEK/ m ² and to put edge on the carpet it costs 120kr/m.

a) What costs a rectangular carpet with the dimension:
2.50m x 3,20m
which will line/fringed/trimmed around)?

b) In the carpet shop it is said that they want to use their computer for printing bills. And to do this kind of thing it needs a formal calculation of the price on lined/trimmed carpets of different length and width. Set up such formula.

4. A truck’s value,
y
SEK, is assumed to be a function of the car’s age,
x
years, according to
y
=750000 · 0, 80exponentX ( IT MEANS 0,80X)

a) How much did the truck cost as new?

b) Justify your answer in a).

c) Describe how the truck’s value changes with its age.

5. Benny controlled the fuel consumption for his car. He noted the distance the car had travelled/passed/ride between each refueling. Later he compiled the results after seven tank refueling in a table.

The table goes like this:

Distance (mil) Gasoline consumption (I)

23,5 29,2

32,0 38,4

45.6 53, 1

28,6 34,8

31,4 36,3

37,2 43,2

42,1 50,5

Observe/examine graphically if the gasoline consumption is proportional to the distance traveled. And if so/ in that case resolve/decide the proportionality constant and specify what it stand for.

6. You fill a thermos with coffee. For this thermos, applies that the temperature drops by 12 % under each two-hour trading period. It is valid under 8 hours from that it has been filled with hot liquid.

a) Type of the table below in your answer sheet and fill in the temperatures that are missing.

Time (hours) Temperature (° C)

0 85

2,0

4,0

6,0

8,0

a) Draw a graph that shows how the coffees temperature
y
°C varies with the time x in hours.

b) Determine/decide from the graph the coffees temperature after 7 hours.

c) Pelle claims that you can calculate changes per hour by sharing 12 % with 2. Is he right or wrong? Remember to justify your answer.