What is the percent decrease from 90 to 45

A change from 45 to 90 represents a positive change (increase) of 100% Use the formula found below on this webpage to find the percent change by replacing the given values: Percent change = [(45 - 90) / 45] x 100 = 100 % (increase) Where: 45 is the old value and 90 is the new value. In this case we have a positive change (increase) of 100 percent because the new value is greater than the old value.

 she will need 273.8 cm 

934mm =93.4 cm

43.5 x 2 = 87

93.4 x 2 = 186.8

add
186.8 + 87 =273.8

Hope this helped!!