Is this really the toughest Mathematics question for class 10 of CBSE?

Is this really the toughest Mathematics question for class 10 of CBSE?

CBSE (Central Board of Secondary Education) is a national-level education board in India controlled by Union Government of India for private and public schools. From 2018, CBSE decided to conduct Board exams for students of class 10 and class 12. Question papers for students come from CBSE only where they make sure that they follow certain rules to make the question papers. For example, question papers should be based on NCERT books only.  

In Mathematics for class 10, the question paper is made in reference to NCERT book only.

If we look upon this book, we see quite number of questions. It depends on person to person, which question seems easy or difficult to one. Though, all questions are easy for everyone if one gives his/her best and studies thoroughly. Some people may be able to solve a particular question whereas some may not. Still, if you go just by CBSE NCERT Mathematics book of class 10, then the most rated question in terms of difficulty is the question 9 from exercise 4.3 of chapter 4 Quadratic Equations which is ‘Two water taps together can fill a tank 9 and 3/8 hours. The tap of larger diameter takes 10 hour less than the smaller one to fill the tank separately. Find the time in which each tap can separately fill the tank.’ Though, it is not so difficult but students find hard to understand and make equations to solve it. Many of the students study this and when it comes to solving, they forget it. This question can be solved like this:
Let the time taken by the smaller diameter tap = x

larger = x-10

total time taken = 75 /8

portion filled in one hour by smaller diameter tap = 1/x

and by larger diamter tap = 1/x-10

1/x + 1/x-10 = 8/75

x-10+x/x(x-10) = 8/75

2x+10/x²-10x = 8/75

8(x²-10x) = 75 ×2 (x-5)

8/2 (x²-10x) = 75 (x-5)

4x²-40x = 75x-375

4x² -40x-75x +375 = 0

4x²-115x + 375 = 0

4x²-100x-15x +375 = 0



x= 25

x= 15/4

If x= 25 

the x-10 = 25-10 = 15

if x = 15/4

x-10 = 15/4 – 10 = 15-40/4 = -25/4

since time cannot be negative therefore x = 25

Answer courtesy: Brainly
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18 thoughts on “Is this really the toughest Mathematics question for class 10 of CBSE?

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