Please enter the following details
Free Daily Targets & Mocks
Study Material & Formulas PDFs
1 on 1 Mentorship
Question 58
If a certain weight of an alloy of silver and copper is mixed with 3 kg of pure silver, the resulting alloy will have 90% silver by weight. If the same weight of the initial alloy is mixed with 2 kg of another alloy which has 90% silver by weight, the resulting alloy will have 84% silver by weight. Then, the weight of the initial alloy, in kg, is
Solution
Let the alloy contain x Kg silver and y kg copper
Now when mixed with 3Kg Pure silver
we get $$\frac{\left(x+3\right)}{x+y+3}=\frac{9}{10}$$
we get 10x+30 =9x+9y+27
9y-x=3 (1)
Now as per condition 2
silver in 2nd alloy = 2(0.9) =1.8
so we get$$\frac{\left(x+1.8\right)}{x+y+2}=\frac{21}{25}$$
we get 21y-4x =3 (2)
solving (1) and (2) we get y= 0.6 and x =2.4
so x+y = 3
Video Solution
Create a FREE account and get:
- All Quant CAT complete Formulas and shortcuts PDF
- 35+ CAT previous year papers with video solutions PDF
- 5000+ Topic-wise Previous year CAT Solved Questions for Free
CAT Quant Questions | CAT Quantitative Ability
CAT Venn Diagrams QuestionsCAT Remainders QuestionsCAT Number Series QuestionsCAT Logarithms, Surds and Indices QuestionsCAT Simple Interest Compound Interest Questions
CAT DILR Questions | LRDI Questions For CAT
CAT Data Interpretation Basics QuestionsCAT Truth Lie Concept QuestionsCAT Maxima-Minima QuestionsCAT 2D & 3D LR QuestionsCAT Charts Questions
