Question

In a test (+5) are given for every correct answer and (-2) marks are given for every incorrect answer. (i) Radhika answered all the questions and scored 30 marks though he had got 10 correct answers. How many incorrect answers had she attempted ?

Answer 1

Answer:

Marks given for one correct answer = 5

So, marks given for 10 correct answers  

= 5 X 10 = 50

Radhika's score = 30

Marks obtained for incorrect answer

= 30- 50 = -20

Marks given for one incorrect answer  

= (-2)

Therefore, number of incorrect answers

= (−20)÷(−2)=10

Answer 2

Answer:

10

Step-by-step explanation:

let the number of incorrect Answers be X

number of correct answer = 10

marks for every correct answer=+5

total marks she got for correct Answers= 5×10= 50

50+(-2)X=30

50 -2x=30

50- 30= 2x

20 = 2x

X= $\frac{20}{2}$

x=10

number of incorrect answer =10