A man mixed 40 Kg. salt at 60 P. per Kg. with 20 Kg. of salt at 72P. a Kg. At what rate per Kg. should he sell it to gain 12P. per kilogram?
Answers
Step-by-step explanation:
Let the amount of the salt to be mixed at 42 paise be x.
Amount of salt at 24 paisa per kg=25kg
Then total Cost price(C.P)=amount×price that is:
(x×42)+(25×24)=42x+600....(1)
There is x with 42 paise price and 25 kg with a different price of 24 paise.
Total amount of salt after mixing=(x+25)kg
Price of mixed salt=40 paisa
Selling price(S.P)=Total amount×price of selling=(x+25)×40....(2)
The profit % given is 25%
Therefore, Profit%=
C.P
S.P−C.P
×100
From equations 1 and 2, we have:
25=
42x+600
[(x+25)×40]−(42x+600)
×100
⇒
100
25
=
42x+600
40x+1000−42x−600
⇒0.25=
42x+600
400−2x
⇒0.25(42x+600)=400−2x
⇒10.5x+150=400−2x
⇒10.5x+2x=400−150
⇒12.5x=250
⇒x=
12.5
250
⇒x=
125
2500
⇒x=20
Hence, the amount of salt to be mixed at 42 paisa rate is 20kg.