Mark Wickens

10 MODE8:DIM:GOSUB500:c$=CHR$(5):x=0
20 CLS:PRINT"Upper probability   N(0,1²)";
30 LOCATE0,1:PRINTc$;"x=";x;"?";:INPUT@10;x:LOCATE0,0
60 LOCATE0,1:PRINTc$;".....";
70 sr=0:GOSUB"LIB0:S6210":GOSUB500:IFsr THEN*
75 IFp THENp=ROUND(p,LOG(ABSp)-6)
80 PRINTc$;"p=";p;:z$=INPUT$(1,@):GOTO30
500 ONERRORGOTO510:RETURN
510 IFERR=1 THENCLS:ONERRORGOTO0
520 IFERL=30 THENRESUME30
530 LOCATE0,1:PRINTc$;"not found";:z$=INPUT$(1,@):RESUME20