What is the smallest number with exactly 14 divisors?
Many numbers can be expressed as the sum of two or more consecutive integers. For example, 15=7+8 and 10=1+2+3+4. Can you say which numbers can be expressed in this way?
Do you know a quick way to check if a number is a multiple of two? How about three, four or six?
The ten numbers in the star total 75.
Each number appears in two "lines".
And there are five lines, making a total of 150. Which implies
the total for each line is 30.
This means that R+I=24 and therefore R=11 and I = 13 (or vice
If R=11 then N=12, H =10 and C=11 which is impossible.
If R=13 then N = 10; H = 12 and C= 9, which is correct.
This problem is taken from the UKMT Mathematical Challenges.