Find the best tutors and institutes for Class 10 Tuition
Q2:
Solve the problems given below.
Represent the following situations mathematically:(i) John and Jivanti together have 45 marbles. Both of them lost 5 marbles each, andthe product of the number of marbles they now have is 124. We would like to findout how many marbles they had to start with.(ii) A cottage industry produces a certain number of toys in a day. The cost ofproduction of each toy (in rupees) was found to be 55 minus the number of toysproduced in a day. On a particular day, the total cost of production wasRs.750. We would like to find out the number of toys produced on that day.
Solve the problems given below.
Represent the following situations mathematically:(i) John and Jivanti together have 45 marbles. Both of them lost 5 marbles each, andthe product of the number of marbles they now have is 124. We would like to findout how many marbles they had to start with.(ii) A cottage industry produces a certain number of toys in a day. The cost ofproduction of each toy (in rupees) was found to be 55 minus the number of toysproduced in a day. On a particular day, the total cost of production wasRs.750. We would like to find out the number of toys produced on that day.
Solution :
Given:
(i) Total marbles with John and Jivanti = $45$. After losing $5$ marbles each, the product of the remaining marbles is $124$.
(ii) Let $x$ be the number of toys produced. The cost of production per toy = $55 - x$. Total cost of production = $Rs. 750$.
To Find:
(i) The initial number of marbles John and Jivanti had.
(ii) The number of toys produced on that day.
Part (i): Solving for Marbles
Step 1: Define variables.
Let the number of marbles John had be $x$.
Since the total number of marbles is $45$, the number of marbles Jivanti had is $(45 - x)$.
Step 2: Formulate the equation based on the condition.
After losing $5$ marbles each:
John's remaining marbles = $x - 5$
Jivanti's remaining marbles = $(45 - x) - 5 = 40 - x$
The product of these is $124$:
$(x - 5)(40 - x) = 124$
Step 3: Simplify the quadratic equation.
$40x - x^2 - 200 + 5x = 124$
$-x^2 + 45x - 200 = 124$
$x^2 - 45x + 324 = 0$ [Rearranging terms to standard form $ax^2 + bx + c = 0$]
Step 4: Solve by factorization.
We need two numbers that multiply to $324$ and add to $-45$. These are $-36$ and $-9$.
$x^2 - 36x - 9x + 324 = 0$
$x(x - 36) - 9(x - 36) = 0$
$(x - 36)(x - 9) = 0$
Therefore, $x = 36$ or $x = 9$.
If John had $36$ marbles, Jivanti had $9$. If John had $9$ marbles, Jivanti had $36$.
Final Answer (i): John and Jivanti started with 36 and 9 marbles respectively.
Part (ii): Solving for Toys
Step 1: Define variables.
Let the number of toys produced be $x$.
Cost of production per toy = $(55 - x)$
Step 2: Formulate the equation.
Total cost = (Number of toys) $\times$ (Cost per toy)
$x(55 - x) = 750$
Step 3: Simplify the quadratic equation.
$55x - x^2 = 750$
$x^2 - 55x + 750 = 0$
Step 4: Solve by factorization.
We need two numbers that multiply to $750$ and add to $-55$. These are $-25$ and $-30$.
$x^2 - 30x - 25x + 750 = 0$
$x(x - 30) - 25(x - 30) = 0$
$(x - 30)(x - 25) = 0$
Therefore, $x = 30$ or $x = 25$.
Final Answer (ii): The number of toys produced on that day was either 25 or 30.
More Questions from Class 10 Mathematics Quadratic Equations EXERCISE 4.2
- Q1(i): Find the roots of the following quadratic equations by factorisation: (i) $x^2 – 3x – 10 = 0$
- Q1(ii): Find the roots of the following quadratic equations by factorisation: (ii) $2x^2 + x – 6 = 0$
- Q1(iii): Find the roots of the following quadratic equations by factorisation: (iii) $\sqrt{2}x^2 + 7x + 5\sqrt{2} = 0$
- Q1(iv): Find the roots of the following quadratic equations by factorisation: (iv) $2x^2 – x + \frac{1}{8} = 0$
- Q1(v): Find the roots of the following quadratic equations by factorisation: (v) $100x^2 – 20x + 1 = 0$
- Q3: Find two numbers whose sum is $27$ and product is $182$.
- Q4: Find two consecutive positive integers, sum of whose squares is $365$.
- Q5: The altitude of a right triangle is $7$ cm less than its base. If the hypotenuse is $13$ cm, find the other two sides.
- Q6: A cottage industry produces a certain number of pottery articles in a day. It was observed on a particular day that the cost of production of each article (in rupees) was $3$ more than twice the number of articles produced on that day. If the total cost of production on that day was ₹ $90$, find the number of articles produced and the cost of each article.
CBSE Solutions for Class 10 Mathematics Quadratic Equations
Chapters in CBSE - Class 10 Mathematics
Top Tutors who teach Quadratic Equations
I enjoy teaching and making things easier and fun for the children. Didn't send my kids for any tuitions. Today the elder child is a CSE graduate , working for Amazon & the other is in her 3rd year MBBS !
I have been studying Maths and Science under her guidance since 8th grade. She explains every concept in a simple and clear way, making even difficult topics easy to understand. Her teaching style is patient and supportive, and she always makes sure all doubts are cleared. She focuses on strengthening basics and gives regular practice, which has really helped me improve. Because of her guidance, my confidence in both subjects has increased a lot. I am truly grateful for her dedication and support
I love to teach students the concepts of Maths and Science. I believe in concept clearance rather than rote learning. Teaching is my passion. Many students have achieved 95 % and more in past years and and I believe that if you join and work hard sincerely, you can also achieved such scores.
Sir explains every concept very clearly and makes sure that i understand each and every point. He teaches slowly and patiently, which makes it easy to follow the class. He also clears my doubts using simple and basic words, so even difficult concepts become easier to understand. His way of teaching helps me build a strong understanding of Science.
Experienced Mathematics and Science Educator | 10+ Years in Teaching and Coaching I have over a decade of experience in teaching and coaching students in Mathematics and Science. I have worked as a PGT Mathematics teacher at GBL Convent School, and have also taught Classes 9 and 10 (Maths & Science) at R.S. Education Hub. My teaching approach focuses on building strong conceptual clarity, personalized attention, and result-oriented strategies to help students excel academically. I have successfully guided numerous students through school exams, board exams, and foundational competitive preparation.
I have worked as PGT teacher in one of the best CBSE schools and all of my students gained more than 90 percent marks. I have full concept of subjects and can assist students in gaining more than 90 percent marks.
Till date taught 1200+ students preparing for board examinations in 10th standard, average result= 98.75% marks. Do you want YOUR child to excel too? Contact me at the earliest!
Find more Tutor for Quadratic Equations in your City
- Bangalore Mathematics Tutors
- Delhi Mathematics Tutors
- Chennai Mathematics Tutors
- Gurgaon Mathematics Tutors
- Noida Mathematics Tutors
- Hyderabad Mathematics Tutors
- Mumbai Mathematics Tutors
- Ghaziabad Mathematics Tutors
- Chandigarh Mathematics Tutors
- Pune Mathematics Tutors
- Jaipur Mathematics Tutors
- Surat Mathematics Tutors
Download free CBSE - Class 10 Mathematics Quadratic Equations EXERCISE 4.2 worksheets
Download Now