SOLR-13105: Improve curve fitting docs 5
diff --git a/solr/solr-ref-guide/src/curve-fitting.adoc b/solr/solr-ref-guide/src/curve-fitting.adoc
index 66dfc3d..06dffb1 100644
--- a/solr/solr-ref-guide/src/curve-fitting.adoc
+++ b/solr/solr-ref-guide/src/curve-fitting.adoc
@@ -53,7 +53,7 @@
The fitted model can also be used
by the `predict` function in the same manner as linear regression. The example below
-uses the fitted model to predict a response time for a files size of 42000.
+uses the fitted model to predict a response time for a file size of 42000.
image::images/math-expressions/polyfit-predict.png[]
