diff --git a/intro_lab/solutions/pi_loop.f90 b/intro_lab/solutions/pi_loop.f90
index 91f5d83bfb3430959ce12a425307233e5aeba593..286da8535e179eebc7d872625be114e741e92098 100755
--- a/intro_lab/solutions/pi_loop.f90
+++ b/intro_lab/solutions/pi_loop.f90
@@ -48,7 +48,8 @@ do num_threads = 1, MAX_THREADS
     pi = step * raw_sum
 
     run_time = OMP_GET_WTIME() - start_time
-    print '(" pi is ", f12.6, " in ", f12.6, " seconds and ", i0, " threads")', pi, run_time, num_threads
+    print '(" pi is ", f12.6, " in ", f12.6, " seconds and ", i0, " threads. Error = ", e15.6)', &
+        pi, run_time, num_threads, abs(3.14159265358979323846D0 - pi)
 
 enddo
 
diff --git a/intro_lab/solutions/pi_spmd_final.f90 b/intro_lab/solutions/pi_spmd_final.f90
index f21b2eace608f435f511bc09377720cd2f421f50..571a32dd0bcdb9441f48210db5785fb8dc890083 100755
--- a/intro_lab/solutions/pi_spmd_final.f90
+++ b/intro_lab/solutions/pi_spmd_final.f90
@@ -58,7 +58,8 @@ do num_threads = 1, MAX_THREADS
 
     pi = step * full_sum
     run_time = OMP_GET_WTIME() - start_time
-    print '(" pi is ", f12.6, " in ", f12.6, " seconds and ", i0, " threads")', pi, run_time, num_threads
+    print '(" pi is ", f12.6, " in ", f12.6, " seconds and ", i0, " threads. Error = ", e15.6)', &
+        pi, run_time, num_threads, abs(3.14159265358979323846D0 - pi)
 
 enddo
 
diff --git a/intro_lab/solutions/pi_spmd_simple.f90 b/intro_lab/solutions/pi_spmd_simple.f90
index 737ca1b0269b9c8d90473fca7302386cf0c09d1b..eb87ddf8206edc483083f1ec6ea8bc28f095575f 100755
--- a/intro_lab/solutions/pi_spmd_simple.f90
+++ b/intro_lab/solutions/pi_spmd_simple.f90
@@ -59,7 +59,8 @@ do num_threads = 1, MAX_THREADS
 
     pi = step * full_sum
     run_time = OMP_GET_WTIME() - start_time
-    print '(" pi is ", f12.6, " in ", f12.6, " seconds and ", i0, " threads")', pi, run_time, num_threads
+    print '(" pi is ", f12.6, " in ", f12.6, " seconds and ", i0, " threads. Error = ", e15.6)', &
+        pi, run_time, num_threads, abs(3.14159265358979323846D0 - pi)
 
 enddo