"A grocer purchased a quantity of bananas..."

[Gatorlilian]

Hi!
This is supposed to be an easy one, but my mind is blocked somehow...
A grocer purchased a quantity of bananas at 3 pounds for $0.50 and sold the entire quantity at 4 pounds for $1.00. How many pounds did the grocer purchase if the profit from selling the bananas was $10.00?
(A) 40
(B) 60
(C) 90
(D) 120
(E) 240

Thanx for your help!

[sanjeev_sharma]

Let grocer purchases X pounds of bananas

therefore the seeling price of all X pounds of banana = X * 1 /4 and the purchasing price is = X * 0.5/3 = X * 1/6

Since the profit is $10 therefore X/4 - X/6 = 10 i.e. X = 120

[Gatorlilian]

I appreciate your help. Thank you!

[manikdhingra]

in such problems u need to make the quantity bought and sold to be same...so u calculate the cost price for 1 pound i.e .5\3 and sellin price for 1 pound=1\4...profit =1\6-1\4=1\12 for 1 pound.....and the total profir to be 10....quantity = 120.