"Find the Mystery Number" and Why I Absolutely Love it

Find the Mystery number has always been a big hit among my students. My own kid loves it and keeps asking for more. This has been a great way to entertain him and his cousins while we were on road trips and at home. They are also popular in math competitions like MOEMS and Math Kangaroo. This post talks about the various ways you can frame questions with it and how it can help your kids as well.

1. Promote growth mindset in kids.

Growth mindset is extremely important in kids. If they are willing to think and learn, they can master anything. It helps them in their adult life too.

Mystery number questions are open ended questions to make them think. Kids learn to make a list, eliminate some responses, and pick the right answer based on the criteria given.

Eg. i) I am a number between 2000 and 8000

My hundreds digit is 6 less than my thousand's digit.

My ten's digit is 6 times my one's digit.

I have no zeros.

What number am I?

2. Practice a variety of topics

A lot of concepts can be practised through Mystery number puzzles. Place value, divisibility rules, multiples, least common multiples etc.

Eg. i) Practicing place value with Find the Mystery Number

I am a 4 digit number.

My hundred's digit is 4 less than my thousand's digit.

My unit's digit is 7 less than my ten's digit.

My ten's digit is 3 more than my hundred's digit.

My thousand's digit is the largest single-digit number.

What number am I?

I've jumbled the order on purpose. I want the kids to figure out what to solve first. Maybe when they start you can give the clues in order.

Eg ii) Practicing divisibility rules and list-making

I am a 2 digit number less than 50.

I am a multiple of 3.

My ten’s digit is 2 more than my Unit’s digit.

What number am I?

Eg iii) Practicing LCM and multiples

I am a 2 digit number.

I am a multiple of 4 and 7.

My ten's digit is twice my unit's digit.

What number am I?

3. The word Mystery gets them excited

Of course throw in the word Mystery and the kids get excited. Take an example of this.

Eg 1) This is so much more fun than asking the kids to just list all the numbers that add upto 10.

I am a 2-digit number.

My digits add upto 10.

My tens digit is 2 more than my Unit's digit.

What number am I?

This question would require them to make a list but in an indirect way and has the fun element to it.

If I ask my kid to make a list of all numbers that add up to 10, he most certainly will crib about it. But this way he does it happily.

4. These can be adapted to almost any age.

From Grade 1 to Grade 8. For the younger kids, they can learn place value. For the Middle and Upper Elementary, they can start their list-making and logical reasoning skills.

Eg i) For Grades 1 and 2 This is how I started my 5-year-old on Mystery Number as well.

I am a 2 digit number.

My ten's digit is 7+2.

My unit's digit is 7-2.