The radius of the front wheel of Lisa's bike is 43cm. Lisa goes for a cycle and travels 56.75km. How many full revolutions did Lisa's front wheel complete?

She completed 210 revolutions

Step-by-step explanation:

Firstly here, we will calculate the distance covered in a single revolution

Mathematically, that is the distance equivalent to the circumference of the circle

That will be ;

2 * pi * r

= 2 * 3.142 * 43 = 270.212 cm

So this is the length of one revolution

Now, we know that ;

1000 cm is 1 km

so x cm is 56.75 km

x = 56.75 * 1000 = 56750 cm

So the number of revolutions in 56750 cm distance will be ;

56750/270.212 = 210 revolutions

to find the perimeter, you add up all the lengths of the sides. in this case you would have to add up 18+22+40+80 which equals 160.