A school has less than students and if the students are divided equally into teams of either or or or each, exactly are always left out. However, if they are divided into teams of each, no one is left out. The maximum number of teams of each that can be formed out of the students in the school is
A school has less than students and if the students are divided equally into teams of either or or or each, exactly are always left out. However, if they are divided into teams of each, no one is left out. The maximum number of teams of each that can be formed out of the students in the school is
Entered answer:
Solution
Let's call the number of students . From the given conditions:
When divided by 9, 10, 12, or 25: remainder is 4
When divided by 11: remainder is 0 (no one left out)
When is divided by 9, 10, 12, or 25, the remainder is always 4. This means that if the actual number was 4 less, it would be perfectly divisible by 9, 10, 12, and 25
is divisible by all of 9, 10, 12, and 25.
Let's find the smallest number that divides 9, 10, 12, and 25.
Prime factorization:
Taking the highest power of each prime factor:
So for some integer .
Therefore:
Now, we need to find a p such that N is divisible by 11 & N < 5000
Since, we know N < 5000, p would be < 5.
As maximum value of p is small, we can find the exact value by trial and error.
904 is not divisible by 11
1804 is divisible by 11
Since we need to find the maximum value, we should check with the remaining too.
When , (Not divisible)
When , (Not divisible)
When , (Not divisible)
Max number of teams of 12 that can be formed:
Hence, the answer is 150.