a) Following are the marks obtained by 20 pupils of a class. Present the marks in frequency table and find the mean marks. 50, 90 70, 80, 50 40, 60, 40, 80, 50, 70, 70, 80 60, 40 70, 50, 70, 60, 70,

Represent the mark on frequency table as follows;

Marks Frequency

40 3

50 4

60 3

70 6

80 3

90 1

Mean= Sum of all the marks

Frequency

(40×3)+(50×4)+(60×3)+(70×6)+(80×3)+(90×1)

20

=2250

20

=11.5

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you

answer: the answer is simply nothing.

step-by-step explanation: because there is no ending to this question

gimme brainliest > : 3