# Monthly Archives: January 2019

## DAY/DYDD 21:

The Main Challenge Which is the lowest whole number that is NOT a multiple of 4, 5 or 6, nor a prime number, square number or cube number? The 7puzzle Challenge The playing board of the 7puzzle game is a 7-by-7 grid containing … Continue reading

## DAY/DYDD 20:

The Main Challenge Consider all whole numbers from 1 to 60, then delete the following:  all prime numbers,  … and any number that differs by 1 from a prime,  all square numbers,  … and any number that differs by 1 from a square, … Continue reading

## DAY/DYDD 19:

The Main Challenge Only one of the following 3-digit numbers is divisible by 3. Which one? 136   139   245   248   353   357   466   469   572   578   680 [Note: If you don’t know the trick on how to work this out, please … Continue reading

## DAY/DYDD 18:

The Main Challenge All nine numbers from 21 to 29 inclusive must be allocated to a letter below so that each allocated number satisfies the condition given on the line:  (a)  even number,  (b)  factor of 144,  (c)  power of 3,  (d)  prime … Continue reading

## DAY/DYDD 17:

The Main Challenge Find the answer to this large number trail which involves fourteen arithmetical steps and includes fraction and percentage calculations. Start with the number 11, then: double it 50% of this +50 subtract thirty-five ÷2 +37 3/5 of … Continue reading

## DAY/DYDD 16:

The Main Challenge What is the sum of the 50 integers (or whole numbers) from 1 through to 50 inclusive? The 7puzzle Challenge The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84. The … Continue reading

## DAY/DYDD 15:

The Main Challenge Your task is to multiply two numbers together and then subtract a third number to achieve the target answer of 7. The three numbers used in each calculation must all be unique digits from 1-9. For example, … Continue reading

## DAY/DYDD 14:

The Main Challenge Insert the 12 numbers 1 1 2 2 2 3 5 5 6 7 8 and 8 so that all three lines work out arithmetically: ◯  +  ◯   =     6     =   … Continue reading