A lump of two metals weighing 18 g is worth Rs. 87 but if their weight is interchanged, it would be worth Rs. 78.60. If the price of one metal be Rs. 6.70 per gram, find the weight of the other metal in the mixture.
A. 8g
B. 12g
C. 15g
D. 18g
Answer: Option A
Solution(By Examveda Team)
Cost of (18g of 1st metal + 18g of 2nd metal) = Rs. 165.60 Cost of (1g of 1st metal + 1g metal of 2nd metal) = Rs. 9.20 Hence cost of 1g of 2nd metal, = 9.20 - 6.70 = Rs. 2.5 Mean price = Rs. $$\frac{{87}}{{18}}$$ Now, $$\frac{{{\text{quantity}}\,{\text{of}}\,{1^{{\text{st}}}}\,{\text{metal}}}}{{{\text{quantity}}\,{\text{of}}\,{2^{{\text{nd}}}}\,{\text{metal}}}}$$ $$ = $$ $$\frac{{14}}{6}:\frac{{56}}{{30}} = 5:4$$ Quantity of 2nd metal = $$\frac{{18 \times 4}}{9}$$ = 8gJoin The Discussion
Comments ( 5 )
Related Questions on Alligation
A. $$\frac{{1}}{{2}}$$ kg
B. $$\frac{{1}}{{8}}$$ kg
C. $$\frac{{3}}{{14}}$$ kg
D. $$\frac{{7}}{{9}}$$ kg
A. 81 litres
B. 71 litres
C. 56 litres
D. 50 litres
solution is not perfect
price of one metal per gram=6.7
price of second metal per gram=p
weight of one metal in mixture=x
weight of second metal in mixture=18-x
before interchange: 6.7*x+p(18-x)=87
after interchange:6.7(18-x)+px=78.6
after solving: p=2.5 ,x=10
so weight of second metal in mixture=8
solution is wrong..it is not according to the question
Is that 18g sum of two metals or is 18g wt of both metals individually?
hw ? 165.60