21.
The average annual income (in Rs.) of certain
agricultural workers is S and that of other workers is T. the number of
agricultural workers is 11 times that of other workers. Then the average
monthly income (in Rs.) of all the workers is:
a)
S + T/ 2
b)
S + 11T / 2
c)
1 /11 S +
T
d)
11 S + T / 12
22.
A family consists of grandparents, parents and
three grandchildren. The average age of the grandparents is 67 years. that of
the parents is 35 years and that of the grandchildren is 6years. What is the
average age of the family?
a)
28 4/7 years
b)
31 5/7 years
c)
32 1/7 years
d)
None of these
23.
A library has an average of 510 visitors on Sundays
and 240 on other days. The average number of visitors pore day in a month of 30
days beginning with a Sunday is:
a)
250
b)
276
c)
280
d)
285
24.
If the average marks of three batches of 55, 60
and 45 students respectively is 50, 55 and 60, then the average marks of all
the students is:
a)
53.33
b)
54.68
c)
55
d)
None of these
25.
The average weight of 16 boys in a class is
50.25 kgs and that of the remaining 8 boys is 45.15 kgs. Find the average weight
of all of boys in the class.
a)
47.55 kgs.
b)
48 kgs.
c)
48.55 kgs.
d)
49.25 kgs.
ANSWERS
