Since the factors all share a common multiple of 360, We can do this:

360/360 + 180/360 + … + 2/360 + 1/360, where the numerators are all the factors and the denominator is 360 all the way. But the sum of the numerators is 1170, so the answer should be 1170/360, and it is, which also simplifies to 3.25

Challenge: what is the sum of the reciprocals of the squares of the factors of 360, given that the sum of the square of every factor of 360 is 201110? Yes, I had to calculate it by hand. 😦

Same thing, but just all the reciprocals are squared. 129600/129600 + 32400/129600 + … + 4/129600 + 1/129600 = 201110/129600 ≈ 1.55177469136

Also, I don’t know if this is for everyone right now, but Google has a weird thing where if you press / it jumps to your search bar, so I thought the Google calculator was broken.

I just used a calculator.

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