In a multiple choice examination of 20 questions, four marks are given for each correct answers and one mark is deducted for each wrong answer. There is no penalty for not attempting a question. a candidate attempts "a" questions and get "c" correct. Write down, and simplify, an expression for the candidate's total mark in terms of "a" and "c".

Step-by-step explanation:

Total no. of questions = 20

Marks given for a correct answer = 4

Marks deducted for a wrong answer = 1

No. of questions attended by the candidate = a

No. of questions the candidate gets correct = c

No. of questions the candidate gets wrong = a - c

Marks obtained for correct answers = 4c

Marks deducted for wrong answers = 1 (a - c)

Total marks scored by the candidate =

Marks obtained for correct answers - Marks deducted for wrong answers

Total marks scored by the candidate = 4c - 1 (a - c)

= 4c - a + c

= 5c - a

3.4 pizzas

step-by-step explanation:

given is a scatter plot showing number of pizzas sold during weeks for different issues of coupon

y represents number of pizzas sold and x number of coupons issued

y is marked verticaly and x horizontally

the trend line is given as

y =3.4x+43

this says that even when no coupon is issued pizzas sold will be 43

and rate of change of pizza sold for 1 unit of coupon = slope = 3.4

i.e. when x increases by 1 unit y increases by 3.4 units

hence for each additional coupon issued 3.4 pizzas more will be sold

you need to show the graph

step-by-step explanation: