Question

Math Problem

Shi-Anne's cottage is on the shores of Circle Lake. Shi-Anne's cottage and Sonja's cottage are on opposite sides of this circular lake. It is a 2.5-km walk along the shoreline between the cottages.
a) How far must Shi-Anne swim across the lake to get to Sonja's?
b) In one hour, Shi-Anne can swim 1.5 km and walk 3 km. Which way is faster?

Answer 1

so 2.5 km is 1/2 the distance around the lake
lake=circle
therefor
2.5=1/2circumference
we must find the circumference to find radius then diameter to find the distnace from one side to the other
2.5=1/2 circumference
multipiliy by 2
5=circumferneece

circumference=2pir or pid
r=radius=distance from middle of circle to outer edge
d=diameter=2 times rasius, or lonest line drawn in circle (we want to find this to see how far it is from one end of the circle to ther other)

5=circumference=pid
5=pid
divide both sides by pi
5/pi=d
aprox pi to 3.14 for the problem
5/3.14=d=1.59 rounded
so
A. 1.59 km

B. 1.5 km per hour swim and 3km per hour walking
we see that 1.59 is greater than 1.5 so it wil take more than 1 hour to swim
we see that 2.5 is smaller than 3 so it will take less than 1 hour to walk
it is faster to walk



A. 1.59 km
B. walking