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Resources tagged with Reading and writing numbers similar to Six Times Five:

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Broad Topics > Numbers and the Number System > Reading and writing numbers

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Six Times Five

Stage: 3 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

How many six digit numbers are there which DO NOT contain a 5?

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Lesser Digits

Stage: 3 Challenge Level: Challenge Level:1

How many positive integers less than or equal to 4000 can be written down without using the digits 7, 8 or 9?

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Mini-max

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

Consider all two digit numbers (10, 11, . . . ,99). In writing down all these numbers, which digits occur least often, and which occur most often ? What about three digit numbers, four digit numbers. . . .

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Lastly - Well

Stage: 3 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

What are the last two digits of 2^(2^2003)?

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The Codabar Check

Stage: 3

This article explains how credit card numbers are defined and the check digit serves to verify their accuracy.

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Sept 03

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

What is the last digit of the number 1 / 5^903 ?


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