Let the price of each note book be Rs.x.
Let the number of note books which can be brought for Rs.300 each at a price of Rs.x be y.
Hence xy = 300
=> y = 300/x
(x + 5)(y – 10) = 300 => xy + 5y – 10x – 50 = xy
=>5(300/x) – 10x – 50 = 0 => -150 + x2 + 5x = 0
multiplying both sides by -1/10x
=> x2 + 15x – 10x – 150 = 0
=> x(x + 15) – 10(x + 15) = 0
=> x = 10 or -15
As x>0, x = 10
Mathematics Mcqs - Maths Mcqs are very important for every test. prepare for NTS, FPSC, PPSC, SPSC, CSS, PMS Test Preparation. and all other testing services. Most of the test syllabus contain Mathematics test portion. Here you will find most important Mathematics Mcqs. here these Mcqs will help you getting good marks in this Section. Here you will find most important Mcqs of Mathematics from Basic to Advance. some of the most important sub categories are: Average, Percentage, Problem on Ages, Time and Distance, HCF and LCM, Logarithms, Discount, Interest, Ratio & Proportion, Decimal Fraction and other.