Answer
There were 17 children, with 11 sweets each.
Reasoning
If we number the clues: each child had more than one sweetthere were more children than there were sweets per child
187 only has the factors 1, 11, 17, 187. Therefore, the only possible answers are:
1 child, with 187 sweets each, which is not allowed by (2)
11 children, with 17 sweets each, which is not allowed by (2)
17 children, with 11 sweets each (*)
187 children, with 1 sweet each, which is not allowed by (1)
Only one possible answer (*) isn't eliminated.
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Puzzle 6
We have been quite lucky with the weather recently, it has got steadily warmer each day, over the last five days.
By this, I mean that the temperature rose by the same amount each day.
The average temperature was 2 °C, and I know it froze on two occasions (0 °C).
I also know the product of the temperatures was over 500 but below 2,000 and each temperature was an integer.
Hint
What must the middle temperature be? Remember that the temperature are in degrees Celsius.
Answer
The temperatures were -6, -2, 2, 6, 10 °C.
Each day increased by a steady 4 degrees.
Reasoning
As the temperature rose steadily each day, we know that the middle temperature (Day 3) was 2 degrees (because the average was 2 degrees).
Since Day 3 was 2 degrees, and there were two negative temperatures, we know that the daily increase must have been at least 3 degrees (otherwise Day 2 would not have been negative).
If we check a daily increase of 3 degrees, the sequence would be -4, -1, 2, 5, 8, but this doesn't work as the product is less than 500.
If we check a daily increase of 4 degrees, the sequence would be -6, -2, 2, 6, 10, which does matches all of the requirements.
If we check a daily increase of 5 degrees, the sequence would be -8, -3, 2, 7, 12, but this doesn't work as the product is more than 2000.
Any larger increase makes the product even larger, so we can stop checking.
So the only possible answer is -6, -2, 2, 6, 10.
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Puzzle 7
At midnight at the start of January 1st, Professor Stone set two old-fashioned clocks to the correct time.
One clock gains one minute every hour, and the other clock loses two minutes every hour.
When will the clocks next show the same time as each other? When will the clocks both show the correct time?
Hint
In order for the clocks to show the same time (e.g. 2 o'clock), what must the total time gained by one, and lost by the other, total?
Answers Midnight, 10 days later, when they will both show 4 o'clock. Midnight, 30 days later, when they will both show 12 o'clock. Reasoning #1
In order for the clocks to show the same time, the total time gained by one, and lost by the other, must be 12 hours.
For example, if the first clock were to show 2 o'clock, it would have gained 2 hours. In order for the second clock to also show 2 o'clock, it would have had to have lost 10 hours. This is a total of 12 hours gained and lost.
We know that for every hour that passes, the first clock gains one minute, and the second clock loses 2 minutes, for a total time gained and lost of 1 + 2 = 3 minutes.
The total time gained and lost will equal 12 hours when 12 x 60 ÷ 3 = 240 hours have passed. 240 hours = 10 days.
The first clock will have gained 240 x 1 minutes = 240 minutes = 4 hours.
The second clock will have lost 240 x 2 minutes = 480 minutes = 8 hours.
So, they will both show 4 o'clock, 10 days later.
Reasoning #2
In the first answer, we can see that 10 days later, the clocks both show 4 o'clock.
If we move forward another 10 days, both clocks would show 8 o'clock.
If we move forward another 10 days, both clocks would show 12 o'clock.
This will now be the correct time.
So, they will both show 12 o'clock, 30 days later.
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Puzzle 8
The legendary BrainBashers calendar had a recent bug. Here is a listing showing the number of days in each month:
January 107
February 68
March 135
April 15
May 133
June 104
July 104
August 16
September ?
Take the first letter of the month, and find its position in the alphabet: S = 19.
Then take the number of letters in the month: September = 9.
January 10 7
February 6 8
March 13 5
April 1 5
May 13 3
June 10 4
July 10 4
August 1 6
September 19 9
