Tugas Membuat Soal Bahasa Inggris

There is a circle-shaped border that is meant to be a safe zone because a big tornado. It's 3 km from the edge of the tornado. From a satelitte measurement, the area of tornado is about 154 km square. So, how much far the safe zone measured from the center of the tornado is?

Answer:

we can measure  it by:
first, we have to find the radius of the tornado. Which is:
22/7 x r x r = 154
r x r = 49
r = 7
and then we add the radius of tornado with 3, so :
3+7 = 10 km
So, the safe zone is 10 km from the center of the tornado.