13 x 1☐ = 20☐ 560 x 7☐ = 4☐560 1☐4 x ☐81 = 54☐14 ☐4 x 3☐1 = 20☐74 ☐92 x 4☐4 = 33☐928 1☐27 x ☐38 = 44☐826

Each red box represents a missing digit.
Can you find out what they are?

## A Mathematics Lesson Starter Of The Day

Topics: Starter | Arithmetic | Problem Solving

• Miriam Candelaria, Toa Baja, Puerto Rico
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• It is fun and a great day starter. I would really appreciate the answer key, though.
• Transum,
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• Thanks Miriam, you'll find the answers to most starters right at the bottom of the page for those who have a Transum subscription.
• Helsby High School, 10y4
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• Most of the class thought this was a good starter. Thank You
• Mrs O'hagan's 3rd Yr Class, Holyrood Sec School Glasgow
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• We enjoyed the activity and would like similar but even more challenging!
• 6LC, West Kidlington Primary School
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• It was quite hard but we really enjoyed it!
• Transum,
•
• What strategies might you use to do this activity? Most people would probably reach for their calculator straight away but the task requires a more thoughtful approach. Each calculation has a different form and different suppositions can be made depending on the digits that are given. Trial and improvement with a planned range of possible missing digits and a calculator used wisely will help solve this puzzle. Each time the page is refreshed a different set of calculations will appear giving plenty of opportunity for practice.

How did you use this starter? Can you suggest how teachers could present or develop this resource? Do you have any comments? It is always useful to receive feedback and helps make this free resource even more useful for Maths teachers anywhere in the world.

Previous Day | This starter is for 1 December | Next Day

 13 x 16 = 208 560 x 76 = 42560 194 x 281 = 54514 54 x 381 = 20574 692 x 484 = 334928 1027 x 438 = 449826

Note to teacher: Doing this activity once with a class helps students develop strategies. It is only when they do this activity a second time that they will have the opportunity to practise those strategies. That is when the learning is consolidated. Click the button above to regenerate another version of this starter from random numbers.

Your access to the majority of the Transum resources continues to be free but you can help support the continued growth of the website by doing your Amazon shopping using the links on this page. Below is an Amazon search box and some items I have chosen and recommend to get you started. As an Amazon Associate I earn a small amount from qualifying purchases which helps pay for the upkeep of this website.

 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).

Transum.org/go/?Start=December1

The 1st December is the date to start opening the doors of the 2021 Mathematics Advent Calendar.