clear;
while [ 1 = 1 ]; do
num1=$((RANDOM%13+0))
num2=$((RANDOM%13+0))
read -p $num1'x'$num2=  ans
let answer=$num1*$num2
cor=$(expr $ans = $answer)
if [ $cor = '1' ];
then echo correct 
else echo wrong;
fi;
seconds=$(date '+%S')
let new=$seconds+3

while [ $seconds != $new ];do
   seconds=""
   seconds=$(date '+%S')
done;

clear;

done;