Latest Bank Exam Aptitude Question SOLUTION: a goldsmith added 10% impurities to 50m of pure gold later he took 25gm of the above gold& added 10gm of pure gold to it what % of impurity was there in the 40gm of gold?

• Placement Papers
• /
• Bank Exam
• /
• Numerical Ability

Bank Exam Question Papers:

(#M40155159) BANK EXAM Numerical Ability question allegation and mixture Keep an EYE

a goldsmith added 10% impurities to 50m of pure gold later he took 25gm of the above gold& added 10gm of pure gold to it what % of impurity was there in the 40gm of gold?

Asked In Bank Exam mini atreya (8 years ago)

Unsolved Read Solution (2)

Is this Puzzle helpful?   (9)   (6) Submit Your Solution

Read Solution (2) :

Varun Aggarwal  (7 years ago)

Gold Impurity Total
50 5 55

Gold:Impurity is 50/5 i.e. 10:1

As 25gms of gold is withdrawn from total of 55, amount of gold left with us is 30gms. As 25 gms of gold is not all pure gold it contains impurity, amount of impurity is 25*(1/11).

Remaining impurity is 5-25/11 = 30/11.

And then question says that 10gm of gold is added so total gold becomes 30+10 = 40gms

Now, this 40 gms of gold contains 30/11 gms of impurity. Now, to find 30/11 gms is what % of 40gms, i do

((30/11)/40)*100 = 75/11 = 6.9%

Is this solution Helpfull? Yes (2) | No (2)  

Devendra Marghade  (8 years ago)

8.33%

(I) with 10% impurities in 50gm. of pure gold: Amount of Gold : Impurities= 50 :5
(II) 25 gm of this gold will contain Gold : Impurities=25*50/55 : 25*5/55=250/11 : 25/11 and
(III) Remaining 30 gm will contain Gold : Impurities=30*50/55 : 30*5/55= 300/11 : 30/11
(IV) As 10 gm of pure gold is added to 25 gm (or mixture II) above, it will contain Gold : Impurities=(250/11)+10 : 25/11= 360/11 : 25/11
(V) Now the total mixture of 65 gm (III+IV) will contain Gold:Impurities=(300/11)+(360/11) : (30/11)+(25/11)
=660/11 : 55/11 i.e % of impurities=100*55/660=25/3=8.33
So 40 gm of gold will contain impurities=40*8.33/100=3.33 gm

Is this solution Helpfull? Yes | No (3)  

Please Login to Read Solution.