Number of cars sold Exam practice
20 A car manufacturer sells diesel, petrol and electric cars.
The composite bar chart shows information about sales over three years.
Key
6000
Diesel
5000
Petrol
4000
Electric
3000
2000
1000-
0
2016 2017 2018
Year
a Write down the number of diesel cars sold in 2016
b Work out the total number of petrol cars sold in the 3 years
(3 marks
c State the type of car that had the greatest increase in sales over the three years
Give a reason for your answer
(2 marks
Mark says, 'in 2018, more electric cars were sold than diesel cars. This means
the manufacturer makes more profit from the sale of electric cars than from the
sale of diesel cars
d Is Mark correct? You must justify your answer
anted from IMF Max 2018 012

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

$4034.40

the perimeter of the field is the sum of the lengths of the four sides:

47 yd + 158 yd + 47 yd + 158 yd = 410 yd

the cost of 3 ft (1 yd) of fence is 3×$3.28 = $9.84.

so the cost of jake's wood perimeter fance is

(410 yd) × ($9.84 /yd) = $4034.40

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116