The radius of the cardboard tube of 85th loop of paper is 4.92cm
The arithmetic sequence is the sequence where every term is increased or decreased by a fixed number from the previous number.
Here the outer radius of the tube is 2.4 cm
the thickness of the paper is 0.3mm= 0.03cm
i.e. in every loop the increase in the radius of the loop is 0.03cm
then the radius in every sequence will be 2.40, 2.43, 2.46, 2.49, 2.52, .....
so here it is clear that it is an arithmetic sequence with a common difference of 0.03.
nth term of the sequence, aₙ = a₁ + (n - 1)d where a₁ is the first term, n is the index of the loop, and d is a common difference.
here a₁ =2.40
d=0.03
n=85
the radius of tube of the 85th loop will be= r= 2.40+(85-1)0.03= 2.40+ 2.52= 4.92
Therefore The radius of the cardboard tube of the 85th loop of paper is 4.92cm
Learn more about the arithmetic sequence
here: brainly.com/question/6561461
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