this uh let’s take this over here real quick and place it right there because it’s the exact same thing except at the end we’re going to use i’m going to show you how to use sum with the x lookup at the same time now we’re going to be using the formula sum and so we’re going to sum and then within the sum our first number is going to be an x lookup and then our next value is also going to be an x lookup so let’s do x lookup and now we’re going to search for our very first value oops our very first lookup value so we’re going to go to i1 and then we’re going to search this again and we want whatever value oops goes into that so let’s close that parentheses and now we’re going to do a colon and another x