PROGRAM BT1_3
	PARAMETER (NMAX=100)
	REAL X(NMAX), TB,P_OVER_TB,P_LOWER_TB,P_OVER_1500
	INTEGER NAM(NMAX),N,I
	OPEN(1,FILE='C:\MASTER\G_TR\BAITAP~1\NEW\BANG1.TXT')
	READ(1,*)
	READ(1,*)
	READ(1,*)N
      READ(1,*)((NAM(I),X(I)), I=1,N)
	TB = AVER(X,N)
	P_OVER_TB = (1.0 - P_LOWER(X,N,TB))*100.0
	P_LOWER_TB = P_LOWER(X,N,TB)*100.0
	P_OVER_1500 = (1.0 - P_LOWER(X,N,1500.0))*100.0
	WRITE(*,'(" LUONG MUA TRUNG BINH R = ",F12.2," (mm)")') TB
	WRITE(*,'("     XAC SUAT P(R > TB) = ",F12.2," (% )")') P_OVER_TB
	WRITE(*,'("     XAC SUAT P(R < TB) = ",F12.2," (% )")') P_LOWER_TB
	WRITE(*,'("   XAC SUAT P(R > 1500) = ",F12.2," (% )")') P_OVER_1500
	END


      FUNCTION AVER(X,N)
C... CHUONG TRINH NAY TINH TRUNG BINH SO HOC CUA CHUOI
C... DU LIEU VAO LA MANG X DO DAI N CHUA SO LIEU QUAN TRAC
C... CUA BIEN NGAU NHIEN X
      INTEGER N, I
      REAL X(N)		! MANG CHUA SO LIEU BAN DAU
      REAL TMP
      TMP = 0.0
      DO I = 1,N
         TMP = TMP + X(I)
      END DO
      AVER = TMP/REAL(N)
      RETURN
      END
c
      FUNCTION P_LOWER(X,N,X0)
C... CHUONG TRINH NAY TINH UOC LUONG XAC SUAT CUA SU KIEN
C... P(X<X0)
C... DU LIEU VAO LA MANG X DO DAI N CHUA SO LIEU QUAN TRAC
C... CUA BIEN NGAU NHIEN X, X0 LA MOT GIA TRI NAO DO
      INTEGER N, N_LOWER, I
      REAL X(N)		! MANG CHUA SO LIEU BAN DAU
      N_LOWER = 0
      DO I = 1,N
         IF (X(I).LT.X0) N_LOWER = N_LOWER + 1
      END DO
      P_LOWER = REAL(N_LOWER)/REAL(N)
      RETURN
      END