Aptitude - Average - Discussion

Ramya. Good way to solve, simple to understand.

I solved in this method.. Is this right?
Let x,y,z be the age of husband,wife and child respectively..
for the first condition.. we can write 27=((x+y+z)/3)-3
27=(x+y+z-9)/3
81=x+y+z-9
90=x+y+z....equation 1
for the second condition..we can write 20=((y+z)/2)-5
20=(y+z-10)/2
40=(y+z-10)
50=y+z........equation 2
equation1 - equation2 gives x+y+z-y-z=90-50
x=40
i.e husband's age is 40years..

((h-3)+(w-3)+(c-3))/3=27
h+w+c=90.
how to 90 comes ? I don't understand.

@priya:
Hi priya. Look into your equation, send 3 to right side which gives the equation, h,w,c are current ages of husband, wife and child respectively....
The average of their ages three years back is as follows.
((h-3)+(w-3)+(c-3))/3=81
==> h+w+c=81+9
==> h+w+c=90 ----(1)(this is the sum of ages of husband, wife and child at present)
And further it is given that, five years back, average of wife and child is 20 years.
i.e. ((w-5)+(c-5))/2=20
==> (w-5)+(c-5)=40
==> w+c=50----(2)

Now, on substituting equation (2) in (1)..
we will get h=90-50 = 40 years.
Hence, the current age of husband is 40 years.
Hope you would get it now.

Thanks ramya.

Its so easy ramya thanks.

Its simple:

Avg of 6 family members before 10 years is (Hus-10)+(wife-10)+(fath-10)+(othrs-30)/6 at 10 years ago.. By simpllifing abv we get (hus+wife+fath+othrs-60)/6

Present age average(Here babe replaces father): (Hus+wif+Babe+others)/6

As per given condition equate both the abv equ: U'll get Father's age=60 years..!! QUITE EASY NA ??

Thanks ramya.

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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

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

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