Question

If the average of the first seven consecutive positive integers is "a" and that of the first nine consecutive positive integers is "b". Then what be the value of the square-root of the squared difference of "a" and "b"?
a. 4
b. 2
c. 3
d. 5

Answer 1

Answer:

A

Step-by-step explanation:

If a, b, c, d and e are five consecutive positive integers. What is the unit's digit of ?

Let the numbers are

a , a + 1(b), a + 2(c), a + 3(d), a + 4(e). =

So, basically a = ?

(1) c = 5

Since a + 2 = 5

a = 3.

SUFFICIENT.

(2) a + b is six less than e + d.

a + b = e + d - 6

Here it's clear that under given condition any value of a, b, e and d would satisfy the equation.

INSUFFICIENT.

Answer A.