To approximate the size of USA in relation to Ethiopia we proceed as follows: Size of Ethiopia GDP in 2017=$ 76.9x10^9 Size of USA GDP=19.6x10^12 thus the scale factor of USA to Ethiopia will be: 19.6x10^12/76.9x10^9 =254.9 this can be written as a whole number to be 255 the economy of US is 255 times that of Ethipia
