24sir the answer which i have in the book is
17 divisors and sum=2066
The number and sum of divisors of the number 1800 which are proper and divisible by 6=
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6 Answers
62number of divisors will be same as no of divisors of 1800/6 = 300 = 22.3.52
no of divisors will be 3.2.3 = 18
62sum of divisors will be
6* ( sum of divisors of 300)
= 6 × (1+2+4)(1+3)(1+5+25)
The proof of this part is not so simple.. but it is waste solving it without the proof!
62try finding the proof for both these parts!
basically it is
= 6 × (1+2+22)(1+3)(1+5+52)
2462That is because they may have excluded the number 1800 (Have they written proper divisors?!)
Ditto with the sum.. they may have substracted 1800 :)
So not a big deal :)
62The sum is a multiple of 6 since each divisor we have to have a multiple of 6..
so this part has a mistake in what is given...