One Digit 100

How many ways can you write an expression for 100 which only uses the same digit repeated and any operations?

One Digit 100


Topics: Starter | Arithmetic | Place Value | Problem Solving | Puzzles

  • Miss Llewellyn’s set one, Rawthorpe
  • (5x5)=25 25-5=20 20x5=100 so (5x5-5)x5
  • OpenGate , Czech Republic
  • Generally: (AAA-AA)/A, you can choose any number between 1-9 instead of A
  • Hannah Loyden (10-3), St John Bosco Liverpool
  • Suggestion is 55 + 55 - 5 - 5 = 100.
  • 10-3, WHGS Manchester
  • Denny(11 x 11) - 11 - 11 + 1 = 100
    Musa (ish) 1 + 1 + 1 etc = 100
    Sammi 55 + 55 - 5 - 5
    Dom 22 x 22 -222 - 222 + 22 + 22 + 22 - 2 - 2 - 2.
  • Hethersett Junior School, Hethersett Junior School
  • 5(5 + 5 + 5 + 5)
    55 + 55 - 5 - 5
    2(22 x 2) + 2 + 2 + 2 + 2 + 2 + 2.
  • Jacob, St John Baptist
  • Another one is 888-88=800*8=100.
  • Saleem Shah, Furness Primary School
  • My name is Saleem and i've got 4 solutions
  • Faiz, Hethersett JUnior
  • (2x2) x 22 +(2x2) + (2x2) + (2x2).
  • Michael, Hethersett Junior
  • 44 + 44 +(44/4) + 44/44.
  • 5x5x5-5-5-5-5-5.
  • St Peter's Y6 Maths, UK
  • We loved this and got loads of good answers - Abi T was our winner.

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One Digit 100

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