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Roger picks two consecutive integers, one of which ends in a 5.
He multiplies the integers together and then squares the result.
What are the last two digits of his answer?
This problem is taken from the UKMT Mathematical Challenges.
Times and Square
Age 14 to 16
ShortChallenge Level 
Roger picks two consecutive integers, one of which ends in a 5.
He multiplies the integers together and then squares the result.
What are the last two digits of his answer?
This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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