Ten students sit a test consisting of 20 questions. Two students get 8 questions correct and one student gets 9 questions correct. The remaining seven students all get at least 10 questions correct and the average number of questions answered correctly by these seven students is an integer. If the average number of questions answered correctly by all ten students is also an integer, then what is that integer?
6 answers
http://www.mathsisfun.com/whole-numbers.html
This is all the info I was given. It was also a question I was given in a math competition that I participated in and the answer is either
A.10
B.11
C.12
D.13
E.14
A.10
B.11
C.12
D.13
E.14
sum for the 7 over 10 must be divisible by 7 and from 77 to 140 by sevens
77, 84 , ...... 105 , 112 ..... 140
that sum + 2*8+9 or 25 must be divisible by 10
LOL 105 !!!
105 + 25 = 130
130/10 = 13
77, 84 , ...... 105 , 112 ..... 140
that sum + 2*8+9 or 25 must be divisible by 10
LOL 105 !!!
105 + 25 = 130
130/10 = 13
even for a contest.
Yes it was a hard question but thank u so much for helping
You are welcome.
4 answers