100 REM TUTOR
120 A=RND(10)+1
130 B=RND(10)+1
140 F=RND(3)
160 PRINT A;
180 GOSUB 500+F*100
250 PRINT
260 PRINT "RESULT";
300 INPUT G
310 IF G=R GOTO 400
320 PRINT "NO, ";A;
330 GOSUB 500+F*100
350 PRINT "=";R;", NOT ";G
360 E=E+1
370 GOTO 120
400 PRINT "CORRECT!"
410 GOTO 120
500 REM ADD
510 PRINT "+";B;
520 LET R=A+B
530 RETURN
600 REM SUBTRACT
610 PRINT "-";B;
620 LET R=A-B
630 RETURN
700 REM MULTIPLY
710 PRINT "*";B;
720 LET R=A*B
730 RETURN