CA Foundation · Quantitative Aptitude · Equations
A shopkeeper in Jaipur sells notebooks and pens. 3 notebooks and 2 pens cost ₹130, while 2 notebooks and 5 pens cost ₹155. What is the price of one notebook?
The price of one notebook is ₹30 according to the key, but the data do not reconcile to a clean solution, so this item is flawed and should be discarded.
- A₹30Correct
- B₹25
- C₹35
- D₹20
Explanation
Let notebook = x, pen = y. 3x + 2y = 130 and 2x + 5y = 155. Multiply the first by 5 and the second by 2: 15x + 10y = 650 and 4x + 10y = 310. Subtracting gives 11x = 340, which is not clean, so recheck: the data used must reconcile. Solving by elimination of x instead: 6x + 4y = 260 and 6x + 15y = 465 gives 11y = 205, also not clean. Hence the stated data are inconsistent with integer prices; this item should not be used.
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