Page 117 - NUMINO Challenge_D1
P. 117
Type 13-1 Increasing Perimeter of a Circle
Imagine utility poles measuring 2 m long are planted on
Earth and connected to each other with one continuous
electric line. How much longer is the length of the
electric line compared to the perimeter of Earth?
(Imagine that the earth is a perfect sphere and that all the poles are on
the same plane.)
1 How much longer is the diameter of the circle connected by electric lines
compared to the diameter of Earth?
2 Let' s say is the diameter of Earth. Write expressions for the perimeter
of Earth and the length of the electric line in terms of .
3 How much longer is the electric line compared to the perimeter of Earth?
4 Henry' s school wants to increase the diameter of the school playground by
1 m. If the playground is in the shape of a circle, how much greater is the
perimeter of the new playground compared to that of the original one?
114 NUMINO Challenge D1
Imagine utility poles measuring 2 m long are planted on
Earth and connected to each other with one continuous
electric line. How much longer is the length of the
electric line compared to the perimeter of Earth?
(Imagine that the earth is a perfect sphere and that all the poles are on
the same plane.)
1 How much longer is the diameter of the circle connected by electric lines
compared to the diameter of Earth?
2 Let' s say is the diameter of Earth. Write expressions for the perimeter
of Earth and the length of the electric line in terms of .
3 How much longer is the electric line compared to the perimeter of Earth?
4 Henry' s school wants to increase the diameter of the school playground by
1 m. If the playground is in the shape of a circle, how much greater is the
perimeter of the new playground compared to that of the original one?
114 NUMINO Challenge D1
