Quantitative Aptitude - Arithmetic Ability Questions

M = 10 days

The ratio of efficiency of M & N are 3 : 2

Hence, the time rquired for N alone = 15 days

=> Required time taken t=by both to complete the work = M x N / M + N 

= 10 x 15/ 10 + 15

= 150/25

= 6 days.

We know that, M1 × D1W1 = M2 × D2W2

Here M1 = 1, D1 = 6 min, W1 = 1 and M2 = M, D2 = 90 min, W2 = 1845

1 × 61 = M × 901845 

=> M = 123

Let initial quantity of milk & water in the mixture are 5x & 4x
2 litres water is added.
Hence,
New quantity of milk & water will be 5x & (4x+2)
ATQ,
5x/(4x+2) = 10/9
x/(4x+2) = 2/9 9x = 8x + 4
x=4
Hence,
New amount of water in the mixture = 4x+2 = (4*4) + 2 = 18 litres.

(300 – 101)/11 = 199/11 = 18 1/11

18 Numbers.

For these type of problems,

Quantity of Diesel remained = q1-pqn   

Here p = 12 , q = 120 

=> 1201-121203 = 120 x 0.9 x 0.9 x 0.9 = 87.48 lit.

Given, Manideep purchases 30kg of barley at the rate of 11.50/kg nad 20kg at the rate of 14.25/kg.

Total cost of the mixture of barley = (30 x 11.50) + (20 x 14.25)

=> Total cost of the mixture = Rs. 630

Total kgs of the mixture = 30 + 20 = 50kg

Cost of mixture/kg = 630/50 = 12.6/kg

To make 30% of profit

=> Selling price for manideep = 12.6 + 30% x 12.6

=> Selling price for manideep = 12.6 + 3.78 = 16.38/kg.

Total number of possible ways = 9C3 = 84 ways

Required atleast one girl in the group of three = total possible ways - ways in which none is girl

None of the members in the group is girl = 6C3 = 20

Therefore, number of ways that at least one member is a girl in the group of three

= 84 - 20

= 64 ways.

These two events cannot be disjoint because P(K) + P(L) > 1.

P(AꓴB) = P(A) + P(B) - P(AꓵB).

An event is disjoint if P(A ꓵ B) = 0. If K and L are disjoint P(K ꓴ L) = 0.8 + 0.6 = 1.4

And Since probability cannot be greater than 1, these two mentioned events cannot be disjoint.