3. ian walks 2 km to his best friend’s house, then walks 0.5 km to the library. he then makes a 2.5 km walk home. the entire walk took him 3 hours. what is his average speed in km/h? show how you got your

Correct answer is km/h

Solution:-

Given that Lan walks 2km to his best friend's house, then walks 0.5km to the library and then he walks 2.5km alone.

So total distance walked by Lan is 2+0.5+2.5 = 5km

And to cover five km, he took three hours.

Average speed means "ratio of total distance covered to time elapsed to cover that distance."

Average speed =

                          =

Hence Lan's average speed is

x = central angle apc = measure of minor arc ac

the two angles x and 30 add to 180, so x+30 = 180 and x = 180-30 = 150. the measure of minor arc ac is 150 degrees.

what we need to do from here is find the circumference and then multiply it by x/360 since there are 360 degrees in a circle. in this case, x = 150, so x/360 = 150/360 = 15/36 = 5/12. the shortest distance along the curve from a to c is 5/12 of the distance around the entire circle (aka circumference)

c = circumference

c = pi*d

c = pi*24

c = 24pi

now multiply this by 5/12 to get

distance along minor arc ac = (5/12)*(circumference)

distance along minor arc ac = (5/12)*(24pi)

distance along minor arc ac = 10pi

the formula you can use is

l = (x/360)*pi*d

with

l = length of minor arc

x = central angle

d = diameter

which essentially is the steps we took though a bit differently.