Question

Mean marks obtained by a student in his five subjects are 78 he secured 80 marks in economics 85 in mathematics 70 in commerce 75 in accountancy find the marks he has secured in English​

Answer 1

Explanation:

Let marks in English be x.

The mean of marks = 78

We know that mean of marks is the sum of all the marks divided by the number of subjects.

Therefore,

(x + 80 + 85 + 70 + 75) / 5 = 78

x + 310 = 78 × 5

x + 310 = 390

x = 390 - 310

= 80

Marks in English are 80.

Answer 2

The marks he has secured in English are:

• Given that Mean marks obtained by a student in his five subjects = 78.

• Marks in economics = 80.

• Marks in mathematics = 85,

• Marks in commerce = 70

• Marks in accountancy = 75

• Marks in English = x,

• Then the formula of the mean = Sum of total marks of subjects

                                                                        Number of subjects

• Therefore,

• X+80+85+70+75 = 78

                      5

  =     x +310  =78         =) x+310 = 390.

              5

• Then x = 390 – 310 = 80 marks.

• He has secured English marks = 80.