Aptitude - Average - Discussion

1. A bus is started from the bustand at 8am and after staying 30min at a destination return back to the busstand.The destination is 27 miles from the busstand.The speed of the bus is 18mph.In return journey the bus travels with 50% fast speed.At what time it is return to the bus stand.

a 11am b 1pm c 11pm d 10am

2. Person who decided to go to the weekend trip should not exceed 8hrs driving a day.Average speed of forward is 40mph.Due to the traffic in sunday in return journey average speed is 30mph.How far he can select a picnic spot?

a 120 b 240 c 360 d 40

3. Find the value of @@+25-++@16,where @ denotes square and + denotes "square root"?

4. In a two dimensional array,X(9,7) with each element occupy 4 bytes of memory, with the address of the first element x(1,1) us 3000.find the address of x(8,5)

Can anyone help me in finding the solution for this problem as soon as possible?

Average of present ages of h,w,c=27+3=30
Average of present ages of w,c =20+5=25

so age of husband = 90-50=40

When the solution is started like this
husband=x,wife=y&child=z
bf4 3yrs x-3+y-3+z-3/3 =27
terefore x+y+z=90--1
bf4 5yrs y-5+z-5/2 =20
terefore y+z=50---2 (1-2)
terefore x=40

Ramya your way of answering this was very good.

husband+wife+child =3 years ago =27 present age =30 (27+3=30)
wife and child = 5 years ago =20 present age=25 (20+5=25)
h+w+c =3*30=90 -- I
w+c =2*25=50 --II
substract(I-II) 90-50=40 year

thanks ramya

h+w+c/3 = 27.
h+w+c = 81.

w+c/2 = 20.
w+c = 40.

h+w+c = 81.

h+40 = 81.

h = 81-40.

h = 40.

Given that average age of husband, wife, child 3 years ago was 27 years
average age of wife child 5 years ago was 20 years.

h+w+c/3 = 27.
h+w+c = 81 it is 3 years ago this is eq1.

w+c = 40 it is 5 years ago then it is convert in to 3 years ago i.e adding 2*2 = 4 therefore w+c=44 eq2.

Eq1-eq2 we get h=37 this is 3 years age so add 3 years to get present age
answer is 40 years.

(3x27)+3 [ 27 is avg. age x 3 family members + 3( ie number years ago) ... Ans comes to 85 years.
(2x20)+5 [ 20 is avg. age of child and mother x 2 + 5( ie number years ago ... Ans comes to 45 years.

Now 85-45 = 40 years.

Is it correct way of solving ?

Present age:

H+W+C=30*3.
W+C=25*2.
....................
ie...,H=40 year.