Question

Twelve students sit for an exam which has a maximum score of 100. The average of the twelve scores achieved by the students in the exam was 95.
What is the minimum mark a student could have scored?

Answer 1

Let me help you get the problem started

(x1 + x2 + x3 + ... + x12) /12 = 95
x1+ x2 + x3 + ... + x12 = 12*95

now use the fact that each xi is between 0 and 100

Answer 2

hint, assume that everyone else (except the worst student) got 100's , what is the worst case scenario ?

Answer 3

Sorry, but i till dont get it, there to much numbers and letters! Sorry!

Answer 4

do you agree that the sum of the scores has to be 12*95

Answer 5

Yeah, i guess!

Answer 6

I am using the definition of average, you have 12 scores that average to 95

(x1 + x2 + x3 + ... + x12) /12 = 95

Answer 7

Ok,

Answer 8

now multiply both sides by 12

Answer 9

(x1 + x2 + x3 + ... + x12) = 12*95
(x1 + x2 + x3 + ... + x12) = 1140

Answer 10

ok now if you have 12 numbers you are adding up that sum to 1140,
and each number is between 0 and 100, what is the minimum score you could get?
the minimum score can't be zero because
0 + 11*100 = 1100 , and that is too small

Answer 11

Im not sure!

Answer 12

but you can have
40 + 11*100 = 1140

Answer 13

Yeah,

Answer 14

that means the other 11 people got 100, and the worst score is 40

Answer 15

Ahh, ok, thanks, sorry if i dont really get what your trying to explain, sorry,

Answer 16

But, thaks, that helped a lot! Thanks

Answer 17

if you want to keep the original fraction,
we have
(40 + 100 + 100 + 100 + ... + 100) / 12 = 95

Answer 18

I have anothe question u might be able to help me again,

Answer 19

\[ \frac{ 11\times100+x }{ 12 }=95\]
1100+x=1140
x=40
40 is the maximum mark for 1 student.

Answer 20

There are 12 white, 30 red and 18 blue lego pieces in a box. What is the largest number of pieces you could draw from the box without taking a white piece?

Answer 21

@Okean 40 is minimum mark for 1 student

Answer 22

Maganda, what is the worst case scenario. you have the bad luck of drawing 30 red , then 18 blue lego pieces before drawing a white lego piece.

Answer 23

For the question, (probability)