November 2012 Logic & Maths Puzzles
1. Happy Birthday (1)
Daniel, my son, is exactly one fifth of my age. In 21 years time, I will be exactly twice his age.
My wife is exactly seven times older than our daughter, Jessica.
In 8 years time, my wife will be three times older than Jessica.
When we first met, (on our mutual birthday) my wife’s age was 72% of mine.
How many years ago was that?
2. Fixture
Five teams in a competition play each other twice.
The top two teams then play best of seven for the premiership.
What is the minimum number of games required to get a winner?
3. Shriek!
2! is called 2 shriek or 2 factorial and is 2 X 1 =2
3! is called 3 shriek or 3 factorial and is 3 X 2 X 1 = 6
What is the value of 6! minus 4! ?
4. Write the binary number 110011 as a decimal number.
5. Happy Birthday (2)
Ray and Peter celebrate the same birthday.
In 2008, Ray was half Peter’s age.
In 2011, Ray’s age reached 60% of Peter’s.
In what year will Peter be 50% older than Ray?
6. Grandma’s House
Sam lives 12 km due South of Grandma’s House.
Kit lives 20 km due North of Bob.
Rose lives 5 km due South of Sam.
Bob lives 10 km due North of Rose.
Cal lives 5 km due East of Sam
Which two of the five live the same distance from Grandma’s house?
What is that distance?
7. Panda Pledge
Four people, (Alan, Beth, Colin and Denise) decided to jointly pledge the $8000 necessary to support a Panda at the Zoo for a year.
Alan pledged twice as much as Beth.
Colin pledged three times as much as Beth
Denise pledged the least, but it was enough to make up the difference.
One of them pledged $1200 dollars.
Can you work out how much each person pledged?
8. Happy Birthday (3)
Betty is twice as old as Ann and four years younger than Chris.
When Ann is as old as Betty is now, Chris will be twice as old as Ann.
How old are Ann, Betty and Chris now?
9. Latin Maths
Add these three Roman numerals and give your answer as a Roman numeral.
LXI IV XXXVIII
10. Sweet Deal
I had some lollies.
I gave 50% of them to Rita, 331⁄3% to Sue, and I kept the last four for myself.
Given that I only gave away whole lollies, how many lollies did Rita and Sue each get?