Gabriel's problem

Gabriel's problem

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Lesson details

Key learning points

  1. In this lesson, you will learn about a famous maths problem called Gabriel's problem.

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6 Questions

A sequence is defined as follows: Start with any positive integer value (𝑛). Each term is found from the previous term as follows: If the value is even, divide it by 2 (𝑛/2). If the value is odd, multiply it by 3 and add 1 (3𝑛+1).
Q2.
If the first term of the sequence is 30, what would the second term be?
100
Correct answer: 15
60
91
Q3.
If the second term of the sequence is 30, what would could the first term be?
100
15
Correct answer: 60
91
Q4.
Fill in the gap: The Collatz conjecture states: no matter the start number (𝑛), the sequence will always reach __________.
half of the start number
infinity
Correct answer: one
zero
Q5.
What is the first name of Mr Collatz?
Bob
Christian
Leonard
Correct answer: Lothar
Q6.
In what year did Collatz make his conjecture?
1927
Correct answer: 1937
1997
2007

3 Questions

Q1.
Each blue box is the product of the 3 numbers in that row or column. All the questions refer to this picture below. First, what is the value in box A?
An image in a quiz
Correct answer: 15
16
9
Q2.
What is the value in box B?
1
Correct answer: 2
3
4
Q3.
Which of the following could be a value for C?
112
189
Correct answer: 72
83

Lesson appears in

UnitMaths / Famous maths problems