We are given
first term is 1
so, 
each succeeding term is found by adding 3 to the one before it
so, common difference is

Since, this is arithematic sequence
so, we can use nth terms formula

now, we can plug values
and we get


................Answer
This should be your answer let me know if I’m wrong or not
Answer:
y = 3
Step-by-step explanation:
4y + 3 = 15 First subtract 3 from each side.
4y + 3 - 3 = 15 - 3 The 3 on the left will cancel.
4y = 15 - 3
4y = 12 Divide each side by 4
4y/4 = 12/4 The 4 on the left will cancel because 4/4 = 1
y = 12/4
y = 3
The answer to the problem is simply the surface area of the paper cone.
The area of a paper snow cone is define as
A = <span>π(r)(r + l )
where :
r = d/2 = 3/2 = 1.5 in
l = 6 in
so
</span>A = π(1.5)(1.5 + 6)
A = 35.34 sq in
so 35.34 sq in of paper are needed to make it
<span>Hope my answer would be a great help for you.
If </span>you have more questions feel free to ask here at Brainly.
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