1.500 (on P), 1.785, 2.490, 2.995, 3.555, 3.905, 0.600, 1.410, 2.510, 2.915, 3.105, 3.995, 0.960, 1.500, 1.675, 2.410, 2.995, 3.615( on Q)RL of P is 590.100m. Calculate the gradient of P Q.(HI Method)

*after reading 3.905 next reading 0.600 is decrease and then increase 1.410

Then 0.600 is entered in FS and 1.410 enter on BS

1. HI=RL of P + BS= 590.100 +1.500= 591.6

2. RL Of point 1= HI – IS of point 1 = 591.6 – 1.785 =598.815

3. RL Of point 2= HI – IS of point 2 = 591.6 – 2.490 =598.11

4. RL Of point 3= HI – IS of point 3 = 591.6 – 2.995 =588.605

5. RL Of point 4= HI – IS of point 4 = 591.6 – 3.555 =588.045

6. RL Of point 5= HI – IS of point 5 = 591.6 – 3.905 =587.695

7. RL Of point 6= HI – FS of point 6 = 591.6 – 0.600 =591

8. Change point= new HI of point 6= RL of point 6 + BS of point 6 = 591 – 1.410=592.41

9. RL Of point 7= HI point 6 – IS of point 7 = 591.6 – 2.510 =589.9

10. RL Of point 8= HI point 6 – IS of point 8 = 591.6 – 2.915 =589.495

11. RL Of point 9= HI point 6 – IS of point 9 = 591.6 – 3.105 =589.305

12. RL Of point 10= HI point 6 – IS of point 10 = 591.6 – 3.995 =588.415

13. RL Of point 11= HI point 6 – FS of point 11 = 591.6 – 0.960 =591.45

14. Change point= new HI of point 11= RL of point 11 + BS of point 11 =591.45– 1.500=592.95

15. RL Of point 12= HI point 11 – IS of point 12 = 592.95– 1.675=591.275

16. RL Of point 13= HI point 11 – IS of point 13 = 592.95– 2.410=590.54

17. RL Of point 12= HI point 11 – IS of point 14 = 592.95– 2.995=589.955

18. RL Of point Q= HI point 11 – FS of point Q = 592.95– 3.615=589.335

Arithmetic check:

∑B.S - ∑F.S = Last RL-First RL

4.41 - 5.175 = 589.335 – 590.100

-0.765 = -0.765

Gradient of PQ = (First RL-last RL) / (Distance PQ) = (590.100-589.335) / 225 = 1 / 294.12

= 1 in 294.12 (falling)