Mirror Maths

Show Mirror Image

Show Mirror Image

Show Mirror Image

Show Mirror Image

Show Mirror Image

Show Mirror Image

Show Mirror Image

Show Mirror Image

The bottom half of some symmetrical calculations are shown above. Can you work out the answers?
Can you make up some other calculations where the calculation and the answer both have horizontal lines of symmetry?

[Teacher: pull down the mirror at the top of the screen to show the top halves of the calculations]

A Mathematics Lesson Starter Of The Day


Topics: Starter | Arithmetic | Puzzles | Symmetry | Transformations

  • Aimee Hamilton, Harrytown Catholic High School
  • 80+101=181
  • Abigail Latham, Swinton
  • Hello.
    Im Abigail Latham From St. Charles Rc Primary School Swinton Manchester
    And I Found That 300+100+300+300=1000
  • Abz :D, St Charles Rc Primary
  • -100+300+300+300=800
  • Alice K, St Matts
  • 100 + 88 +111 +1 = 300.
  • Primary 7, Bargeddie Primary School
  • We enjoyed this starter, especially since one of our groups are studying symmetry...
    Here are some of our examples:
    333 - 333 + 1 = 1
    33 x 3 + 1 = 100
    11 x 3 = 33
    111 - 111 + 8 = 8
    Callum in our class also noticed that multiplying any combination of multiples of 10 would give a symmetrical answer:
    e.g. 1000 x 1000, 1 000 000 000 x 1000, 10 x 100 000 000 000 etc.
  • Mr. T, Gartree High School
  • Good for younger groups like year 7s since the sums are pretty straight forward but they liked trying to work out how to reflect the digits.
  • Tomiloba Awosika, Bishop Challoner School
  • Tomiloba from Bishop Challoner School 8B3 has come up with an example - 300 + 300 + 300 - 100 = 800.
  • Prendergast, Prendergast 9.1 Maths
  • 11 + 11 + 11 = 33
    11 + 11 + 38 + 10 + 10 = 80
    8 x 1 = 8
    11 x 3 = 33
    11 x 8 = 88
    13 + 18 = 31
    3 x 1 = 3
    1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 = 8
    1 + 1 + 1 = 3
    symmtrical number x 0 = 0.
  • Elliot, 7X3WO
  • 10+0=10.
  • Octavia Pullman, London School Of Rock, London
  • 30+8= 38.

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Previous Day | This starter is for 10 March | Next Day



l l + 38 = 49

88 x 33 = 2904

838 - 383 = 455

l 8 l x l l = 1991

3 l + 3 l + 3 l = 93

l 0 x l 0 l + l l l = 1121

l 8 l x l 3 l - 80 = 23631

l 380 + 38 - 83 = 1335


Your next challenge is to make an equation with a horizontal and a vertical line of symmetry or a mathematical ambigram

Ambigrams were made famous in Dan Brown's novel "Angels and Demons"

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Laptops In Lessons

Teacher, do your students have access to computers?
Do they have iPads or Laptops in Lessons?

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

Laptops In Lessons

Here a concise URL for a version of this page without the comments.


Here is the URL which will take them to an activity about rotational symmetry.


Student Activity



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