Question

Find the unknown frequency if the mean of the data is 53 and total observation is 100.

plz guys help me​

Answer 1

Answer:

29

Step-by-step explanation:

No. of people

(f) x

i

=

2

lower limit + upper limit

x

i

f

i

0-20 15 10 150

20-40 f

1

30 30f

1

40-60 21 50 1050

60-80 f

2

70 70f

2

80-100 17 90 1530

Σf

i

=53+f

1

+f

2

Σf

i

.x

i

=2730+30f

1

+70f

2

Given:- Σf

i

=100

⇒53+f

1

+f

2

=100

⇒f

1

+f

2

=100−53

⇒f

1

+f

2

=47⟶eq.(i)

Given:- Mean =

Σf

i

Σx

i

.f

i

=53

⇒

100

2730+f

1

+f

2

=53

⇒273+f

1

+f

2

=530

f

1

+f

2

=257⟶eq.(ii)

from eq. (i) & (ii), we get

f

1

=18,f

2

=29

⇒f

1

=18,f

2

=29

Answer 2

Answer:

sorry'don't know this answer.

Step-by-step explanation:

sorry