Darlene averaged a score of 70 out of 110 on evaluations

Question

Darlene averaged a score of 70 out of 110 on evaluations from 1/3 of her supervisors. If Darlene wishes to average a score of 90 out of 110 on all her evaluations, by approximately what percent must her average score increase on the remaining 2/3 of the evaluations?

20% 28% 30% 43% 50%

20% 28% 30% 43% 50%

leonidas · Answer

Let her total number of evaluations be 12.

For 1/3rd => sum = 4*(7/11) = 28/11
For 12 Evaluations=> sum = 12*(9/11) = 108/11
For 2/3rd => sum = (108/11) - (28/11) = 80/11

Average of 2/3 evaluations = (80/11)/(8) = 10/11

% Increase = |7-10|/7 = 42.6% = ~43% Hence (D)

paddler123 · Answer

Ans IMO 28%
Target for 3 eval: 90*3 = 270
1st eval = 70
to get: 200 in 2. Average = 100
so score need sto increase by 30, percentage increase is 30/110 = 27.2727 ~ 28%

leonidas · Answer

It is asked to calculate the average score increase.

paddler123 · Answer

That shows how not to read a question

I read it as 1 supervisors of the 3 gave him so much... how much should 2 of the 3 supervisors give... :oops:

x2suresh · Answer

70/3+ x 2/3 = 90 ----x= 100

average score increase = 100-70/70 = 43%

Darlene averaged a score of 70 out of 110 on evaluations

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