9:50 Puzzle

Can you make this statement true by adding just one small line?

Nine Fifty

Topics: Starter | Puzzles

  • Carol Lowry, Sheffield Park Academy
  • Wednesday, May 16, 2007
  • "Make this sum correct by adding one straight line


    Answer 545+5=550
    Many others similar of course!"
  • R Rees,
  • Tuesday, May 25, 2010
  • "One pupil did 10 10 10 ≠ 9:50 which I thought was excellent."
  • Millicent, Martham Primary School
  • Sunday, May 30, 2010
  • "This was a big brain teaser it made me work really had but I did it in the end. I think that you should try this one because it really gets you going for the rest of the day!!!"
  • Paul Trickett, Prt1960@hotmail.com
  • Sunday, December 12, 2010
  • "My Puzzle is as follows....
    Move one Digit in this sum to make it correct...
    103 - 102 = 3
    103 - 102 = 3.

    Great idea Paul. It has been created as an animation below. Transum"
  • Prince Of Maths, West Yorkshire
  • Tuesday, May 17, 2011
  • "Once, there was a prince called Bob. His father said to him:-
    I rode into town on Friday, stayed for 3 days, and rode back out on Friday, how did I do it?"
  • S2 Maths Class Holyrood, Holyrood Secondary
  • Thursday, May 26, 2011
  • "Qaisar solved this in two seconds. We all thought this was great!! Mrs Boussouara's S2 maths class rules!!R.O.F.L."
  • Rhys, Barclay Primary
  • Wednesday, May 2, 2012
  • "How do you make this true. 1-1=2 just one line
    A. 1+1 =2."
  • , Emily
  • Tuesday, May 29, 2012
  • "103-2=11
    Move one number
    A: 13-2=11."
  • Kieran, Icknield
  • Wednesday, May 30, 2012
  • "Can you find the right answer, by moving 1 line?
    what do you think?"
  • Maths N Laughs, Yate, S Glos
  • Wednesday, May 30, 2012
  • "How about this one,
    The solution to sinx = nx is x = 6, can you work out how?
    The answer is to simply divide both sides by n:
    si x = x
    A little maths joke I hope you agree!"
  • Rebecca Wathen, Worfield Primary School
  • Wednesday, May 30, 2012
  • "0.5 = 1 - 2
    Move two items in this number sentence to make it correct.
    Answer 0.5 = 1/2."
  • Reilly Stallard-Gorton, Worfield
  • Wednesday, May 30, 2012
  • "103 + 104 = 1207
    Move 1 number to make this true.
    You have to move the 1 from the instructions to the beginning of the calculation!
    1103 + 104 = 1207."

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This starter has scored a mean of 4.2 out of 5 based on 177 votes.

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Can you make up a puzzle like this? An equation or identity which is not true but can be made true by adding a line or a point. Your puzzle can be featured on this page. Enter your puzzle here.

Laptops In Lessons

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Do they have Laptops in Lessons or iPads?

Whether your students each have a TabletPC, a Surface or a Mac, this activity lends itself to eLearning (Engaged Learning).

Laptops In Lessons

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