In a town 25% families own a phone and 15% own a car, 65% families own neithers a phone nor a car. 2000 families own both a phone and a car. Consider the following statement in this regard.
(i) 10% families own both a car and a phone.
(ii) 35% families own either a car or a phone.
(iii) 40000 families live in the town.
Which of the above statement are correct?

3739 + 164 x 27 = ?
? = 3739 + 4428 = 8167 ? 8200

There are 12 letters in the world 'civilization' of which four are i's and other are different letters.
? Total number of permutations = 12!/4!
But one word is civilization itself.
? Required number of rearrangements = 12!/4! - 1

We may choose 1 officer and 5 jawans or 2 officers and 4 jawans ......... or 4 officers and 2 jawans.

So Required answer = [⁴C₁ x ⁸C₅] + [⁴C₂ x ⁸C₄] + [⁴C₃ x ⁸C₃] + [⁴C₄ x ⁸C₂]
= 224 + 420 + 224 + 28 = 896.

Let ages of man and his son are 8k yr and k yr, respectively .
According to the question,
(8k + k)/2 = 27
? k = (27 x 2)/9 = 6
Hence, age of son after 6 yr = 6 + 6 = 12 yr

We know that, ⁿP_r = ⁿC_rr!
? ⁿP_r = 720ⁿC_r
? ⁿC_r.r! = 720ⁿC_r
? r! = 720
? r = 6

As per figure we can calculate the ration as below.
Number of supervisors / Number of labourers = (10 / 100) = 1/10
Total number of labourers = Total no. of supervisors × 10
= 15 × 10 = 150.

If the required fraction be N.
Then, (N x N) / (1/N) = 18²⁶/₂₇
? N³ = 512 / 27
? N = 8/3 = 2²/₃