Quantitative Aptitude - Arithmetic Ability Questions

Let the leak will empty the tank in x hrs 

Then, 1/9 - 1/x = 1/13

x = 29.25 hrs

We can initially arrange the six boys in 6! ways.
Having done this, now three are seven places and six girls to be arranged. This can be done in ⁷P₆ ways.

Hence required number of ways = 6! x ⁷P₆

Suppose they meet after 'h' hours

Then

3h + 4h = 17.5

7h = 17.5

h = 2.5 hours

So they meet at => 4 + 2.5 = 6:30 pm

Cost of each cake P1 & P2 = Rs. 12

Offer decrease in % = 20%

Increase in sale per day (Q2) = 250 - 18%

Total quantity per day (Q1) = 250

Hence, required change total revenue

TR = P2Q2 - P1Q1 = (12 x 0.8 x 250 x 1.18) -  (12 x 250) = - Rs.168.

The cow can graze an area of 2826 sq.m i.e it is able to cover area of circle of 2826 sq.m

Therefore, πr2 =2826
r2 =(2826×7/22) = 899.18 = 900
r = 30 m.

Therefore, the radius of the circle implies the length of the rope = 30 mts.

6,400 gents, 2400 ladies in that company.
So total 8,800employees.
for 8,800 employees, we want 2400 ladies.
for 12,100employees we want how many ladies ?
=> (12,100/8,800) x 2400 = 3300.
So we want 3300 - 2400 = 900 more ladies.

Let CP = 100,
42 % increase => SP = 142
10 % discount in SP => ((142 x 10)/100) = 14.2
So 1st SP = (142 - 14.2) = 127.8, again 12 % discount in 1st SP ((127.8 x 11)/100) = 14.058
2nd SP = (127.8 - 14.058) = 113.742,
So finally CP = 100, SP = 113.742, => gain = 13.742%.

circumference of a circle = 2πr

=> 2 × 22/7 × r – r = 37

=> 37/7 × r = 37

=> r = 7 cm.

Diameter D = 2r = 7×2 = 14 cm.