The Ideal Ratio: Find My 156

"Miw" got the topic of the report on "The Ideal Ratio of lover match is 1.09 times" Miw is 170 cm. tall and the way to prove that the theory is true or not, Miw asks "Elle", the girl next door because she 156 cm. tall. For help to prove this theory 1.09 times.
(Source: H'Our Channel YouTube)