Extrapolating is a common word used in various fields like statistics, mathematics, and science. However, if you need to use a synonym for extrapolating in your writing, there are several options available. If you want to convey the idea of extending or projecting forward from a known data point, you can use words like extending, forecasting, or projecting. Similarly, if you want to express the notion of deducing or inferring information from existing data, you can opt for words like inferring, deducing, or deriving. There are many other synonyms available for extrapolating, but the key is to choose the one that best conveys the desired meaning based on the context of your writing.