Elitmus Exam Numerical Ability Permutation and Combination

Raj wants to buy 7 floors in an 68 storied building whose numbering stars from 1 upto 68.but it has to follow certain rules which are as follows

1)none of the floor should be a prime number

2)none of the digit of the floor should be a prime number

3)Raj cannot buy the 1st floor as it is being assigned to the architect.

SO how many options are left with Raj to buy the floor

option)
1). 11
2). 13
3). 15
4). 17

Read Solution (Total 17)

Elitmus Other Question

Statement (1) – 15 Litres of Milk was sold at cost price after adding 20% water.
Statement (2) – Milk was purchased at Rs. 16 per litre.

Options
(a) Mark A
(b) Mark B
(c) Mark C
(d) Mark D
How many 5 digit number can be formed out of digits 0,2,4,6,8 that is divisible by 8.

1. 26 2. 30
3. 38 4. 96