fixed formula for Fourth year, high ability group.

public/index.js

@@ -193,7 +193,7 @@ function calculateReadingTime() {
                 x = (0.3445 * C) + (1315.1448 * 0.357) - 459.0464;
                 break;
             case '42':
-                x = (0.2003 * C) + (51421.0975 * 0.206) - 290.0477;
+                x = (0.2003 * C) + (1421.0975 * 0.206) - 290.0477;
                 break;
             case '43':
                 x = (0.2289 * C) + (1389.9964 * 0.24) - 325.0492;