Mathematics
Junior Mathematical Challenge
2023
13

13

Four congruent rectangles are arranged as shown to form an inner square of area 20 cm2 and an outer square of area 64 cm2. What is the perimeter of one of the four congruent rectangles?

A. 6 cm

B. 8 cm

C. 9.75 cm

D. 16 cm

E. 20 cm

Answer

D. 16 cm

SOLUTIOn

The outer square has area 64 cm2, so its side-length is 8 cm.

Therefore the sum of the length and the breadth of one of the four congruent rectangles is 8 cm.

Hence the perimeter of one of these rectangles is 2 × 8 cm = 16 cm.

(Note that the perimeter of one of the rectangles depends only on the area of the outer square.)

Previous
Next

Subscribe to receive updates!

Be up-to-date with our recent updates, new problems and answers!

Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

Our courses

Mathematics
Programming
Chess
Geometry
Curriculum Mathematics
Mathematics
Online
8+

Curriculum Mathematics

Our goal at this course is to enhance our students’ mathematical intuition by focusing on a deep understanding of mathematical concepts and to enable them to link different concepts and apply their knowledge to solve mathematical problems to help them to improve their performance at Maths exams.

Olympiad Mathematics
Mathematics
Online
8+

Olympiad Mathematics

Olympiad Mathematics is a comprehensive course designed to help students win UKMT competitions. It is suitable for high-achieving mathematics students who are looking to take their skills to the next level.

Introduction to Python with Turtle
Programming
Online
9+

Introduction to Python with Turtle

This course guides you through the fundamentals of Python programming using an interactive Python library known as Turtle.

Coding in Python
Programming
Online
8+

Coding in Python

Python is a versatile and widely-used programming language that is particularly well-suited for beginners. It is known for its simplicity and readability, making it a great choice for students who are new to coding.

Data Science
Programming
Online
16+

Data Science

This course is designed for those with little or no prior programming or data science experience, but who are eager to learn how to use Python to analyze and visualize data.

Chess
Chess
Online
7+

Chess

Supercharge your potential by studying chess alongside maths and programming. Boost strategic thinking, problem-solving, and concentration. Unleash your competitive edge and unlock endless possibilities in these fields.

Olympiad Geometry
Geometry
Online
12+

Olympiad Geometry

This course encompasses a range of Geometry topics such as coordinate and spatial geometry, introductory trigonometry, angles, parallel lines, congruent and similar triangles, polygons, circles, the Pythagorean Theorem, and more. Emphasis will be placed on reinforcing Algebra skills and enhancing critical thinking through problem-solving in both mathematical and real-world contexts.

Get ready for olympiads with free problems, extracurricular topics and our courses

Mathematics

Learn more

Programming

Learn more
Where do you hold your classes?
We hold our classes online or on-site on Saturdays at our branch in Pimlico Academy, London.
You can find our timetable here.
What do you need to start learning online?
For lessons you only need a computer or phone with a microphone, camera and Internet access. Wherever you are - in London, Nottingham, New York or Bali - online lessons will be at hand.
When can I take the introductory lesson?
You can get acquainted with the school at any time convenient for you. To do this, just leave a request and sign up for a lesson.
I can't attend class, what should I do?
It is OK, it happens! Students have the opportunity to cancel a lesson up to 8 hours before the scheduled time without loss of payment. So you can reschedule it for a convenient time, and the teacher will have the opportunity to
I don't have much free time, will I have time to study?
Learning can take place at your own pace. We will select a convenient schedule and at any time we will help you change the schedule, take a break or adjust the program.
How long is one lesson?
All classes last 1 hour.
Hear from some of our amazing students who already achieved incredible results with us!
"Olympiad Maths Lessons helped me a lot to get the Gold medal in Junior Maths Challenge"
St. Paul's Student
"Thanks to the 'Data Science' and 'Coding in Python' lessons I got accepted to my dream university."
Michael
Data Science Student
Warwick University
"Great courses, which thoroughly explained topics beyond the capability of the GCSE answer sheet. Thanks so much."
Ivan
GCSE Student in Dubai
"Financial Mathematics! Best course to understand Python and Mathematics behind Finance!"
Gleb
VC Investor
"We got silver in PMC! Thanks George!"
Mum of St. Paul's Student
Prepare for the Primary Maths Challenge
"My daughter took a batch of 10 classes with George to understand Python with Turtle. I found George extremely knowledgeable and accessible."
Dad of Latymer School Student
Python with Turtle

Contact us

Email

george@exactscience.co
‍

Phone

Mon-Sun from 8am to 9pm
+44 77 07 547 144

Office

Come say hello at our office HQ.
84 Eccleston Square, Pimlico, London SW1V 1NP, UK

...or ask us anything

Smaller 3D model of a student sitting at his desk and preparing for competitions, exams and olympiads.

Ask about our courses and offerings, and we will help you choose what works best for you.

Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

© 2024 All Rights Reserved.