IBPS RRB Office Assistant 26 Sep 2015 Paper

(4) Let the four natural numbers be a, b, c and d.
According to the question,
a + b + c = 180
b + c + d = 197
c + d + a = 208
and, d + a + b = 222
On adding all of these,
3(a + b + c + d) = 180 + 197 +208 + 222 = 807
⇒a+b+c+d=

807

3

=269
∴ Required average
=

a+b+c+d

4

=

269

4

=67

1

4