Separated Twins

Separated Twins

Clue 1

The combination is a six digit number.

Clue 2

There are two ones separated by one other digit.

Clue 3

There are two twos separated by two other digits.

Clue 4

There are two threes separated by three other digits.

A Mathematics Lesson Starter Of The Day


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That was easy! Here's the real challenge!

The combination of the Transum safe is a 14 digit number.

The two 7s are separated by seven other digits;
The two 6s are separated by six other digits;
The two 5s are separated by five other digits;
The two 4s are separated by four other digits;
The two 3s are separated by three other digits;
The two 2s are separated by two other digits;
The two 1s are separated by one other digit.

Separated Twins Interactive
Click here for an interactive version.

Starter of The Day Transum Mathematics Topics


Topics: Starter | Logic | Puzzles

  • 9k1, Kettlethorpe High School
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  • other answers, ************** ************** ************** and **************
  • Transum,
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  • Well done 9k1, Kettlethorpe High School. I wonder if that is all possible answers? Note that answers in the comments are hidden for all but Transum subscribers.
  • Mrs. Peacock, Downe House School and Kennet School
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  • My year 8's absolutely loved the "Separated Twins" starter. I set it as an optional piece of work for my year 11's over a weekend and one girl came up with 3 independant solutions.
  • Sohana, Gateway Academy
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  • Students found **************
  • Lana, Lindsworth North, Birmingham, UK
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  • We found another solution: ************** (Which is also my phone number!)
  • Mr Smith, Durrington High School, Worthing
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  • Starter of the day 18th September. Other possible answers which class 11Y1 found are: ************** and **************
  • Chloe Beames, Broadoak W-s-M
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  • I found **************
  • Sam Yr 8, Broadoak Weston-Super-Mare
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  • I found this one ************** and **************
  • Mr Hamshaw-Hart, Beverley Grammar School
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  • Year 11 top set also found ************** and **************
  • Miss K Smith, Wildern School
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  • My Year 11m1 class found one solution ************** They thought it was silly but actually all had a go.
  • Wednesfield High School, JSS
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  • Top set year 9 got 2 solutions: ************** and **************
  • 8H1, Helenswood School
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  • **************
  • Wednesfield High, JSS
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  • Our Year 8 students discovered this solution to separated twin **************
  • Ross West & Friends, Sleaford
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  • We got ************** from Y11 at St.George's, Sleaford.
  • Curtis, 7
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  • Other Solutions: ************** ************** and **************
  • Sevgi, London
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  • Another solution **************
  • Harrytown High School, 9A2
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  • ************** Adrien Parr ************** Ross Scrivener and Charlotte Baile ************** Antoine Parrythese all work backwards too!
  • Mr Ian Rowe, United Kingdom
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  • Year 11 class at Royal Alexandra and Albert School, UK, with the help of James got **************
  • 8X3, MSJ
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  • Twintastic. This really got the group thinking and Billy really enjoyed it. Jamie was the first to solve the problem.
  • Year 6, Stamford Green Primary School
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  • 4 children came up with the same solution o ************** It was a fab experience!
  • Mr Hudson, King Richard School
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  • Year 9 set 1 **************
  • Ross Roberton, International School Of Luxembourg
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  • Tamas H was the fastest to solve this and won an amazing sweet **************
  • Mr Aveyard, Garforth Community College
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  • We found this activity a challenge but interesting at the same time.
  • Mrs Barnett And 8x1 & 8y1, Bredon Hill Middle School
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  • My Year 8 group have managed to find ************** (found by Archie ************** (found by Jamie)and of course they both work in reverse!
  • Confused, .com
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  • Is there any logic to it? My pupils were asking me - and I just assumed it was trial and error at the time, but now I'm thinking there might be a logical method?
  • Mr N Parrett, Staffs
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  • The class also found the second solution to the original problem ****** is also correct.
  • Andrew Evers, Y6EV - St Giles
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  • My class of 10 year olds found 2 possibilities to the 6 digit combination. The answer you gave ****** and one you didn't mention ******
  • Hannah, Bolton
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  • I also got the answer of ****** which is the reverse of ******
  • Maths Is Fun,
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  • Find a 10 digit number where the first digit is how many zeros in the number, the second digit is how many ones in the number, the third digit is how many twos are in the number etc.
  • Transum,
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  • The combination locks on safes should really be called permutation locks because it does matter which order the digits are entered.

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Laptops In Lessons

Teacher, do your students have access to computers such as tablets, iPads or Laptops?  This page was really designed for projection on a whiteboard but if you really want the students to have access to it here is a concise URL for a version of this page without the comments:

Transum.org/go/?Start=September18

However it would be better to assign one of the student interactive activities below.

Laptops In Lessons

Here is the URL which will take them to a student version of this activity.

Transum.org/go/?to=twins

Student Activity

 

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