The lower bound and upper bound for Helen's value would be; 3.165, and 3.065.
<h3>What is circumference?</h3>
The circumference is the perimeter of the circle.
Given that the circumference of circle C, at 405 mm to three significant numbers.
Helen correctly estimates the diameter of circle, d, to be 130 mm to two significant numbers.
She wants to find the value of Pi using the formula π=C/D
We have, the circumference of the circle, C = 405 mm
The diameter of the circle, d = 130 mm
π=C/D
π= 405 mm / 130 mm
= 405 / 130
π= 3.115 measured to the nearest 0.1.
The degree of accuracy is nearest 0.1.
Then;
0.1/2 = 0.05
Therefore, Upper bound = 3.115 + 0.05 = 3.165
Lower bound = 3.115 - 0.05 = 3.065
Therefore, the lower bound and upper bound for Helen's value would be; 3.165, and 3.065.
To learn more about circumference, refer to the below link:
brainly.com/question/14717074
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