1. Theformulaforcalculatinganindexnumbershouldbesuchthatitgivesthesameratiobetweenonepointofcomparisonandtheother,nomatter whichofthetwoistakenasthebaseorputtingitanotherway,theindexnumberreckonedforwardshouldbereciprocaloftheonereckonedbackwards'whichtest ofconsistencyofindexnumberisthis?