Quantitative Aptitude - Arithmetic Ability Questions

Two painters can complete two rooms in two hours.So 18 rooms can be painted in 6 hrs by 6 painters

Let the speed of the boat upstream be p kmph and that of downstream be q kmph

Time for upstream = 8 hrs 48 min = 845hrs

Time for downstream = 4 hrs

Distance in both the cases is same.

=> p x  845= q x 4

=> 44p/5 = 4q

=> q = 11p/5

 Now, the required ratio of Speed of boat : Speed of water current

= q+p2:q-p2

=> (11p/5 + p)/2  : (11p/5 - p)/2

=> 8 : 3

nS= C4 12=495

nE= C28×C14=112

∴P(E)=112495

a = 12×15×12 = 90 sq.cm  

b = 2a = 12×20×h  

h= 18cm

Let 'x' be the cost price.
Now Marked price = x + 30x/100 = 13x/10
10% discount = 10/100 x 13x/10 = 13x/100
Selling price = 13x/10 - 13x/100 = 117x/100
Given gain = 340
Here gain = 117x/100 - x = 17x/100 = 340 => x = Rs. 2000.

Let the length of the train be L metres and speeds of the train Arun and Sriram be R, A and S respectively, then 

       LR-A=36 ---------- (i) 

and LR+K=24 ---------(ii)

From eq.(i) and (ii)

              3(R - A ) = 2 (R + K) 

⇒  R = 3A + 2K 

In 30 minutes (i.e 1800 seconds), the train covers 1800R (distance) but the Arun also covers 1800 A (distance) in the same time. Therefore distance between Arun and Sriram, when the train has just crossed Sriram

               = 1800 ( R - A) - 24 ( A + K)

 Time required = 1800(R-A)-24(A+K)(A+K)

= (3600 - 24) = 3576 s                            

Let the speeds of the two trains be x m/sec and y m/sec respectively.

Then, length of the first train = 27 x meters, and

length of the second train = 17 y meters.

(27 x + 17 y) / (x + y) = 23

=> 27 x + 17 y = 23 x + 23 y

=> 4 x = 6 y

=> x/y = 3/2.