Workers with the surnames Baker, Teacher, Carpenter, and Plumber are currently attending an annual convention.
No-one is currently, nor has ever been, in the same occupation as their name, and no-one has had the same occupation twice. Charlie has never been a carpenter, and Mr Teacher is now a plumber. Davie used to be a teacher, but Mr Billie Baker never has. Mr Plumber is not called Eddie, and Mr Carpenter wasn't previously a teacher. The previous occupations were all different, and the current occupations are all different.
Can you determine the full names of each of the attendees, along with their current and previous occupation?
The previous occupation is followed by the current.
Reasoning
The four forenames are: Billie, Charlie, Davie, Eddie.
The four surnames are: Baker, Teacher, Carpenter, Plumber
The four occupations are: baker, teacher, carpenter, plumber.
By (3), we have Billie Baker:
Billie Baker – ? + ?
Teacher – ? + ?
Carpenter – ? + ?
Plumber – ? + ?
By (2), Mr Teacher is currently a plumber:
Billie Baker – ? + ?
Teacher – ? + plumber
Carpenter – ? + ?
Plumber – ? + ?
By (3) Mr Baker was not previously a teacher. By (4), neither was Mr Carpenter. And by (1) Mr Teacher can't have been either. Therefore, Mr Plumber used to be a teacher, and is called Davie:
Billie Baker – ? + ?
Teacher – ? + plumber
Carpenter – ? + ?
Davie Plumber – teacher + ?
By (3), Mr Baker has never been a teacher, and by (1), Mr Plumber can't currently be a teacher either. Also, by (1), neither can Mr Teacher. Therefore, Mr Carpenter must currently be a teacher:
Billie Baker – ? + ?
Teacher – ? + plumber
Carpenter – ? + teacher
Davie Plumber – teacher + ?
By (1), Mr Baker can't be a baker, so only Mr Plumber can currently be a baker. Leaving Mr Baker as a carpenter currently:
Billie Baker – ? + carpenter
Teacher – ? + plumber
Carpenter – ? + teacher
Davie Plumber – teacher + baker
By (1), only Mr Teacher could have previously been a carpenter:
Billie Baker – ? + carpenter
Teacher – carpenter + plumber
Carpenter – ? + teacher
Davie Plumber – teacher + baker
By (2), Charlie has never been a carpenter, and since Mr Teacher has, Charlie must be Mr Carpenter.
Billie Baker – ? + carpenter
Teacher – carpenter + plumber
Charlie Carpenter – ? + teacher
Davie Plumber – teacher + baker
By (1), we now know all of the occupations, and Eddie must be Mr Teacher:
Billie Baker – plumber + carpenter
Eddie Teacher – carpenter + plumber
Charlie Carpenter – baker + teacher
Davie Plumber – teacher + baker
?
Puzzle 203
In the illustration we have a sketch of Sir Edwyn de Tudor going to rescue his love, who was held captive by a neighbouring wicked baron.
Sir Edwyn calculated that if he rode at fifteen miles an hour he would arrive at the castle an hour too soon, while if he rode at ten miles an hour he would get there just an hour too late.
Now, it was of the first importance that he should arrive at the exact time appointed, in order that the rescue that he had planned should be a success, and the time of the tryst was five o'clock, when the captive would be taking afternoon tea.
The puzzle is to discover exactly how far Sir Edwyn de Tudor had to ride.
Sir Edwyn De Tudor, Amusements In Mathematics, Henry Ernest Dudeney.
If Sir Edwyn left at noon and rode 15 miles an hour, he would arrive at four o'clock, which is an hour too soon. If he rode 10 miles an hour, he would arrive at six o'clock, which is an hour too late. But if he went at 12 miles an hour, he would reach the castle of the wicked baron exactly at five o'clock, which is the time appointed.
The text above is the answer given in the book, and below is a method of finding the answer.
If we call the distance to the castle, D and use the fact that Time = Distance ÷ Speed, we have:
Travelling at 15 mph:
Time1 = D ÷ 15 (an hour too soon)
Travelling at 10 mph:
Time2 = D ÷ 10 (an hour too late)
The time gap between these two times is 2 hours, therefore
Time2 − Time1 = 2
D ÷ 10 − D ÷ 15 = 2
Multiply throughout by 30:
3D − 2D = 60
D = 60 miles.
??
Puzzle 204
Here are some less well known proverbs. What is the missing word in each?
Loyalty is worth more than ?.
He that cannot pay in ? must pay in person.
Shameful ? is worse than shameful eating.
Don't say ? until you are asked.
Payment in advance is ? payment.
Answer
Loyalty is worth more than money.
He that cannot pay in purse must pay in person.
Shameful leaving is worse than shameful eating.
Don't say no until you are asked.
Payment in advance is evil payment.