diff --git a/05-cache/cache.tex b/05-cache/cache.tex
index 90ba6c831255074b5a35015961ec83b341d2b917..339f76e0276117f712034d3e1b60f1082fd42b9e 100644
--- a/05-cache/cache.tex
+++ b/05-cache/cache.tex
@@ -114,7 +114,7 @@ some of the blocks could be already present in the cache.
\subsection{Mergesort}
The traditional choice of algorithm for sorting in external memory is Mergesort. Let us
-analyze it in our models. Merging of two sorted arrays involves three sequential
+analyze it in our models. Merging two sorted arrays involves three sequential
scans: one for each source array, one for the destination array. The scans are
interleaved, but so we can interleave their I/O operations. We need 1~block of
internal memory for each scan, but let us generally assume that $M/B \ge c$