Quantitative Aptitude - Arithmetic Ability Questions

C alone can finish the work in 40 days.
As given C does half as much work as A and B together
=> (A + B) can do it in 20 days
(A + B)s 1 days wok = 1/20.
A's 1 days work : B's 1 days Work = 1/2 : 1 = 1:2(given)
A's 1 day’s work = (1/20) x (1/3) = (1/60) [Divide 1/20 in the raio 1:2]
B's 1 days work = (1/20) x (2/3) = 1/30
(A+B+C)'s 1 day's work = (1/60) + (1/30) + (1/40) = 9/120 = 3/40

All the three together will finish it in 40/3 = 13 and 1/3 days.

Since their HCFs are 7, numbers are divisible by 7 and are of the form 7x and 7y

Difference = 14
=> 7x - 7y = 14
=> x - y = 2

product of numbers = product of their hcf and lcm
=> 7x * 7y = 441 * 7
=> x * y = 63

Now, we have
x * y = 63 , x - y = 2
=> x = 9 , y = 7

The numbers are 7x and 7y
=> 63 and 49

Other number = 11×7700275= 308

The mathematical formula for calculating compound interest depends on several factors. These factors include the amount of money deposited called the principal, the annual interest rate (in decimal form), the number of times the money is compounded per year, and the number of years the money is left in the bank.

 FV=p1+rnnt

FV = Future value of the Deposit

p = Principal or Amount of Money deposited

r = Annual Interest Rate (in decimal form )

n = No of times compounded per year

t = time in years

FV=40001+0.0644(5)= 5387.42

Each of the 10 letters can be posted in any of the 5 boxes.

So, the first letter has 5 options, so does the second letter and so on and so forth for all of the 10 letters.

i.e. 5*5*5*….*5 (upto 10 times) = 5 ^ 10.

                                              A     +      B        =      C     +     D 

                                              |              |                 |             | 

    Ratio of efficiency         10x   +    5x               9x     +   6x 

                                             |________|                 |_________|   

                                                   15x                           15x 

Therefore , ratio of efficiency of A:C  =10:9 

Therefore,  ratio of days taken by A:C = 9:10 

Therefore, number of days taken by A = 18 days