Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
Solve it the standard way once — then learn the shortcut.
Q · Mixture and AlligationMedium · 45s
There are two kinds of alloys of silver and copper. The first alloy contains silver and copper such that 93.33% of it is silver. In the second alloy there is 86.66% silver. What weight of the first alloy should be mixed with some weight of the second alloy so as to make a 100 kg mass containing 90% of silver?
TopicMixture and Alligation
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Final Answer: Option B — 50 kg