Quantitative Aptitude - Arithmetic Ability Questions

Given are the two AP'S:

15,12,9.... in which a=15, d=-3.............(1) 

-15,-13,-11..... in which a'=-15 ,d'=2.....(2)

now using the nth term's formula,we get

a+(n-1)d = a'+(n-1)d'

substituting the value obtained in eq. 1 and 2,

15+(n-1) x (-3) = -15+(n-1) x 2

=> 15 - 3n + 3 = -15 + 2n - 2

=> 12 - 3n = -17 + 2n

=> 12+17 = 2n+3n

=> 29=5n

=> n= 29/5

A:B:C = (10×7):(12×5):(15×3)

         = 70 :60 :45

         = 14 :12 :9

C's rent = Rs.(175×9/35)

            =Rs. 45.

Given 56% of 225 + 20% of 150 = ? - 109

we know that a% of b = b% of a

Now,

225% of 56 + 20% of 150 = ? - 109

200% of 56 + 25% of 56 + 20% of 150 = ? - 109

112 + 14 + 30 = ? - 109

? = 112 + 14 + 30 + 109

? = 264

the next 2 number in series we need to divide the series into 2 different series

First series : 4 , 6, 12, 30 ??

Second Series : 12,18,26, ??

So we need to see for the pattern for those series in order to find the next two number , we can do this by finding the difference or division , multiplication logic whatever may apply :

• Pattern of Series 1 :

6 divide 4 : 1.5

Next number i.e 12 divided by 6=2

Next number i.e 30 divided by 12 =2.5

So series is going in multiples of 1.5, 2, 2.5, 3 , so on

So first series will look like

4 , 6, 12, 30, 30x3 =90

• Pattern of Series 2 : 12,18,26, ??

Its simple Adding numbers with iterative logic (i.e 6, 8, then followed by 10, 12)

Series will be like 12,18,26,36.

For the next two numbers : Series will be like 4, 12, 6, 18, 12, 26, 30, 36, 90

Part filled in 4 minutes =4(1/15+1/20) = 7/15

Remaining part =(1-7/15) = 8/15

Part filled by B in 1 minute =1/20 : 8/15 :: 1:x 

x = (8/15*1*20) = 1023min = 10min 40sec

The tank will be full in (4 min. + 10 min. + 40 sec.) = 14 min. 40 sec

Let S.P. of 45 lemons be Rs. x.

Then, 80 : 40 = 120 : x or   x = 40×12080= 60

For Rs.60, lemons sold = 45

For Rs.24, lemons sold  =4560×24= 18.

let length = x and breadth = y then  

2(x+y) = 46         =>   x+y = 23  

x²+y² = 17² = 289  

now (x+y)² = 23² 

=> x²+y²+2xy= 529 

=> 289+ 2xy = 529

=> xy = 120  

area = xy = 120 sq.cm