A nationwide test taken by high school sophomores and juniors has three sections, each scored on a scale of

20

to80

.In a recent year, the national mean score for the writing section was48.4

,with a standard deviation of9.9

. Based on this information, complete the following statements about the distribution of the scores on the writing section for the recent year.

(a)According to Chebyshev's theorem, at least56

%

of the scores lie betweenand

.

(Round your answer to 1 decimal place.)

(b)According to Chebyshev's theorem, at least89

%

of the scores lie between28.6

and68.2

.