📖 What IMUCET Tests from Arithmetic
Listen up, cadet. In the engine room, we don't have time for complex calculus when a fuel tank is overflowing or we need to calculate the bunker consumption for the next leg. We use quick, mental arithmetic. That is exactly why IMUCET tests you on basic Arithmetic under General Aptitude. They want to see if you can think on your feet when the pressure is on. This section is not about high-level math; it is about speed, accuracy, and spotting patterns instantly.
Most candidates fail here because they treat these questions like a 5-mark board exam question. They start writing long equations, defining 'x' for everything, and waste three minutes on a single mark. On a ship, wasting time gets you into trouble. In the exam, it gets you rejected. You need to learn the shortcuts, understand the core ratios, and solve these in under 45 seconds.
🎯 IMUCET Focus
IMUCET specifically targets high-yield arithmetic topics: Ratios and Mixtures (like fuel blending), Profit and Loss, Simple and Compound Interest, and basic Work-Time or Speed-Distance problems. They love questions where a mixture is replaced by another liquid, or where you have to find the percentage markup to get a specific profit. Master these four areas and you secure the bulk of your aptitude marks.
MARKS WEIGHTAGE
Typical number of questions from Arithmetic in IMUCET is 3-5 questions.
🧠 Key Concepts
The Constant Quantity Rule in Mixtures
When you remove a mixture and replace it with only one component, the quantity of the other component remains unchanged in ratio to the total. Always equate the part that was NOT added to solve the equation instantly.
Markup and Discount Relationship
Remember that Selling Price = Cost Price * (100 + Profit Percent)/100 = Marked Price * (100 - Discount Percent)/100. Equating these two gives you the direct ratio of Marked Price to Cost Price.
SI and CI Difference for 3 Years
The difference between Compound Interest and Simple Interest for 3 years is given by the direct formula: Difference = P * (r/100)^2 * (3 + r/100). Memorize this to avoid calculating three years of interest manually.
⚡ What to Skip
If you are running out of time and the exam is just two weeks away, you can safely skip complex Compound Interest calculations for variable rates and multi-variable partnership problems. Focus entirely on Ratios, Percentages, and Profit & Loss as they yield the maximum questions.
🏆 Exam Strategy
First, always look at the options before solving; many arithmetic questions can be solved backward by plugging the options into the question. Second, do not write down every step; use scratch paper only for final calculations to save precious seconds. Third, if a word problem takes more than 4 lines to read, skip it and come back to it at the end of the section.
✅ Quick Check — Before You Practice
Answer these 3 questions to confirm you understood the key concepts above.
Q1. A trader marks his goods 20% above the cost price and allows a discount of 10% on the marked price. What is his net profit percentage?
Q2. A sum of money doubles itself in 8 years under simple interest. In how many years will it triple itself?
A. 12 years
B. 16 years
C. 24 years
D. 20 years
Q3. The ratio of copper and zinc in an alloy is 5:2. If 1.5 kg of zinc is added to 17.5 kg of this alloy, what will be the new ratio of copper to zinc?