typeset -i mCnt=0
typeset -i mSeq=1
mOutFile='Total1'
for mFName in `find . -type f`
do
  cat mFName >> $mOutFile
  mCnt=$mCnt+1
  if [ ${mCnt} -eq 10 ]; then
    mSeq=$mSeq+1
    mOutFile='Total'$mSeq
    mCnt=0
  fi
done

# Script file: concat.sh

shopt -s extglob # Not need for ksh

src_prefix=File
out_prefix=Total

typeset -i src_seq out_seq

for src_file in ${src_prefix}+([0-9])
do
   src_seq=${src_file#${src_prefix}}
   (( out_seq=src_seq/10+1 ))
   echo "cat ${src_file} >> ${out_prefix}${out_seq}"
done

$ ls File*
File1  File100  File11  File19  File2  File9  File91  File92  File99
$ concat.sh
cat File1 >> Total1
cat File100 >> Total11
cat File11 >> Total2
cat File19 >> Total2
cat File2 >> Total1
cat File9 >> Total1
cat File91 >> Total10
cat File92 >> Total10
cat File99 >> Total10$