echo problem

echo "XXXXX" >> /xx/output.txt
cat /xx/file.txt| awk '{tony=tony+$1+$2; print tony/$3*100}' >> /xx/output.txt

Dear all,
In this situation i will have 2 lines in the output file. What i want is to have only one output line. e.g: XXXXX "value"

HOW to put the output of the "cat and awk" in the same line after the echo

anyone can help me....

Many thanks;
TONTAL

use

echo "XXXXX\c" >> /xx/output.txt