Quantitative Aptitude - Arithmetic Ability Questions

4, 14, 24, 34, 44, 54, 64, 74, 84, 94 => has 11 number of (4's)
40, 41, 42, 43, 45, 46, 47, 48, 49 => has 9 number of (4's)
So, totally (11 + 9 = 20) number of 4's in 1 to 100.

PW = Amount1+R100T=28001+121002   = Rs.2500 

TD = Amount - PW = 2800 - 2500 = Rs.300

In one day work done by K = 1/20

Work done by K in 2 days = 1/10

Work done by K,L,M on 3rd day =1/20 + 1/30 + 1/60 = 1/10

Therefore, workdone in 3 days is = 1/10 + 1/10 = 1/5

1/5th of the work will be completed at the end of 3 days.

The remaining work = 1 - 1/5 = 4/5

1/5 of work is completed in 3 days

Total work wiil be done in 3 x 5 = 15 days.

As water costs free, water sold at cost price of milk gives the profit.

Required profit % = 5/20 x 100 = 5 x 5 = 25%.

As per divisibility rule a number is divisible by 6 means it should be divisible by 2 and 3

case 1 : the divisibility rule for 2 is the number should be end with even number
in this case R =2 & R=4

case 2 : The divisibility rule for 3 is the sum of numbers should be divisible by 3
so if we take option (2) Q=1 & R=4 the sum is 39
if we take option (3) Q=1 & R=2 the sum is 37

So Option (2) is correct 39 is divided by 3

Total number of balls = 2 + 3 + 4 = 9

Total number of ways 3 balls can be drawn from 9 = 9C3

No green ball is drawn = 9 - 3 = 6 = 6C3

Required number of ways if atleast one green ball is to be included = Total number of ways - No green ball is drawn

= 9C3 - 6C3

= 9x8x7/3x2  -  6x5x4/3x2

= 84 - 20

= 64 ways.