Does anyone know the correct answer to this question?

A box and whiskers plot has the minimum at the end of the left whisker, the 25th percentile at the left edge of the box, the median at the line in the middle, the 75th percentil at the right edge of the box, and the maximum at the end of the right whisker.

Armed with that, let's go through the choices.

A. 3/4 of the data is less than 65. TRUE, 65 is the indicated 75th percentile, which means that 75% or 3/4 of the data is less than 65.

B. The median of the upper half of the data is 65. TRUE. It's an unusual way to phrase it, but the 75th percentile is the middle value of the data from the 50th percentile to the maximum, i.e. the median of the upper half of the data.

C. The interquartile range is 55. That's FALSE. The interquartile range is the difference between the 75th percentile and the 25th percentile, here 65-40=25.

D. The median of the data is 55. The median is the line in the middle of the box, TRUE.

C

see explanation

step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

remove brackets and collect like terms

13 - r - 1 + r

= 12 - r

c

remove brackets and collect like terms

= - 8 - r + 2r - 4

= - 12 + r

d

remove brackets and collect like terms

= 7r - - - 6r

[-   - = - - = - ]

= r -

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.