Mathematics IV
Mathematics IV
Mathematics IV
PACING
1. A 45m course, AB, on level ground was paced by a surveyor for
the purpose of determining his pace factor. The number of paces
for each trial taken are shown in the accompanying tabulation.
Requirements:
a. Determine his pace factor
b. If the surveyor then took 771,770,768,770,772 and 769 paces in
walking an unknown distance CD, what is the length of the line?
c. Determining relative precision.
SOLUTION:
a. Given: L = 45 m; n1 = 6
c. TD = 667m
PD = 666.1 m
RP = (TD - TP) / TD = (667 – 666.1) / 667
= 0.9 / 667
= 1/741 say 1/700
2. In five trials of walking along a 90m course on fairly level
ground, a pacer for a survey party counted 51, 52.5 , 51.5 , 52.5 ,
and 51.5 strides respectively. He then started walking an unknown
distance XY in four trials which were recorded as follows: 88.5,
89, 88, and 87 strides. Determine the following:
a. Pace factor of the pacer
b. Length of line XY
c. Percentage of error in the measurement if the taped length of XY is
150.5 meters
a. Given: L = 90m
n1 = 5
SUM1 = (51+52.5+51.5+52.5+51.5) = 259 strides or 518 paces
M1 = SUM1 / n1 = 518 / 5 = 103.6 paces
PF = L / M1 = 90 / 103.6 = 0.869 m/ paces
b. n2 = 4
SUM2 = (88.5+89+88+87) = 352.5 strides or 705 paces
M2 = SUM2 / n2 = 705 / 4 = 176.25 paces
PD = L / M2 = 770 (0.865 / pace) = 666.1 m
c. TD = 150.5m
PD = 153.2m
DMDab = 47.27
∑DA = - 3,430,192.54
THEREFORE:
2 X AREA = - 3430192.54
DPD ab = 490.71
∑DA = 3,430,192.56
THEREFORE:
2 X AREA = 3,430,192.56
Adjusted
Line Lat (ft) Dep (ft)
AB -176.386 -438.574
BC +203.382 -73.105
CD +192.340 +198.635
DE -219.336 +313.044
Starting with line AB and use Equation (G-4) to compute the DMDs.
ROD AT
NORTHERN 3.54m 2.02m 0.49m
APPROACH
Solution:
ElevA = HI + Vertical Elevation
Difference – Rod Reading
ElevA = HI + {s * (sin 2α) / 2} –
Rod Reading
ElevA = 105.00 + {100 * (sin 2(-
12)) / 2} – 8.00
ElevA = 105.00 + (-20.34) – 8.00
= 76.66’
IV. COMPASS AND TRANSIT RULE
1.) COMPASS RULE. Given in the accompanying tabulation are the
observe data for a traverse. Compute linear closure and precision and
adjust the latitudes and departures using the Compass Rule. Tabulate
values accordingly.
N63o59'20"W
B
S75°W
N14o43'29"W
COMPUTED COMPUTED
COURSE DISTANCE BEARING LATITUDE DEPARTURE
+N -S +E -W
S 36°00'00"
AB 379.25 - 306.82 222.918 -
E
S 75°23'18"
BC 408.90 - 103.152 - 395.675
W
N
CD 298.65 14°43'29" 288.842 - - 75.909
W
N
DA 276.55 121.28 - 248.538 -
63°59'20" E
1,363.35 m + 410.122 - 409.972 +471.456 -471.584
SUMS (Length of
(Σ NL) (Σ SL) (Σ ED) (Σ WD)
Traverse)
AB DE
495.85 m 1,020.87 m
FA
660.08 m
EF
1,117.26 m
AZIMUTH AZIMUTH
COURSE LENGTH FROM COURSE LENGTH FROM
NORTH NORTH
AB 495.85 m 5o30’ DE 1,020.87 m 167o35’
BC 850.62 m 46o02’ EF 1,117.26 m 263o44’
CD 855.45 m 112o22’ FA 660.08 m 304o51’
Solution:
a.) Computing latitudes:
Latab = 495.85 cos 5o30’ = +493.57 m
Latbc = 850.62 cos 46o02’ = +590.53 m
Latcd = 855.45 cos 112o22’ = -325.53 m
Latde = 1,020.87 cos 167o35’ = -996.99 m
Latef = 1,117.26 cos 263o44’ = -121.96 m
Latfa = 660.08 cos 304o51’ = +377.19 m
b.) Computing departures:
Depab = 495.85 sin 5o30’ = +47.53 m
Depbc = 850.62 sin 46o02’ = +612.23 m
Depcd = 855.45 sin 112o22’ = +791.09 m
Depde = 1,020.87 sin 167o35’ = +219.51 m
Depef = 1,117.26 sin 263o44’ = -1,110.58 m
Depfa = 660.08 sin 304o51’ = -541.70 m
c.) Tabulated Solution:
AZIMUTH COMPUTED COMPUTED
COURSE DISTANCE FROM LATITUDE DEPARTURE
NORTH +N -S +E -W
AB 495.85 m 5o30’ 493.57 47.53
BC 850.62 m 46o02’ 590.53 612.23
CD 855.45 m 112o22’ 325.53 791.09
DE 1,020.87 m 167o35’ 996.99 219.51
EF 1,117.26 m 263o44’ 121.96 1,110.58
FA 660.08 m 304o51’ 377.19 541.70
+1,670.3 -
SUMS 5,000.13 m +1,461.29 -1,444.48
6 1,652.28
d.) Determining total closure in latitude and departure.
CL = ΣNL + ΣSL
= +1,461.29 + (-1,444.48)
= +16.81 m (Total Closure in Latitude)
CD = ΣED + ΣWD
= +1,670.36 + (-1.652.28)
= +18.08 m (Total Closure in Departure)
𝐶𝐿
e.) Determining corrections for latitude: Kl = ; cl = Lat (Kl)
ΣNL− ΣSL
16.81 16.81
Kl = = = 0.000579
+1,461.29−(−1,444.48) 2,905.77
Cab = 493.57 (0.000579) = 2.86 m
Cbc = 590.53 (0.000579) = 3.42 m
Ccd = 325.53 (0.000579) =1.88 m
Cde = 996.99 (0.000579) = 5.77 m
Cef = 121.96 (0.000579) = 0.70 m
Cfa = 377.19 (0.000579) = 2.18 m
𝐶𝐷
f.) Determining corrections for departure:K2 = ;cd = Dep(Kl)
ΣED− ΣWD
18.08 18.08
K2 = = = 0.00544
+1,670.36−(−1,652.28) 3,322.64
Cab = 47.53 (0.00544) = 0.26 m
Cbc = 612.23 (0.00544) = 3.33 m
Ccd = 791.09 (0.00544) = 4.31 m
Cde = 219.51 (0.00544) = 1.19 m
Cef = 1,110.58 (0.00544) = 6.04 m
Cfa = 541.70 (0.00544) = 2.95 m
g.) Determining adjusted latitudes:
Adj. Latab = + (493.57 - 2.86) = +490.71 m
Adj. Latbc = + (590.53 – 3.42) = +587.11 m
Adj. Latcd = - (325.53 + 1.88) = -327.41 m
Adj. Latde = - (996.99 + 5.77) = -1,002.76 m
Adj. Latef = - (121.96 + 0.70) = -122.66 m
Adj.Latfa = + (377.19 – 2.18) = +375.01 m
h.) Determining Adjusted departures:
Adj. Depab = + (47.53 – 0.26) = + 47.27 m
Adj. Depbc = + (612.23 – 3.33) = + 608.90 m
Adj. Depcd = + (791.09 – 4.31) = +786.78 m
Adj. Depde = + (219.51 – 1.19) = +218.32 m
Adj. Depef = - (1,110.58 + 6.04) = -1,116.62 m
Adj. Depfa = - (541.70 + 2.95) = -544.65 m
i.) Tabulated Solution:
ADJUSTED
CORRECTION ADJUSTED LATITUDE
COURSE DEPARTURE
LAT DEP +N -S +E -W
AB 2.86 0.26 490.71 47.27
BC 3.42 3.33 587.11 608.90
CD 1.88 4.31 327.41 786.78
DE 5.77 1.19 1,002.76 218.32
EF 0.70 6.04 122.66 1,116.62
FA 2.18 2.95 375.01 544.65
BACKSIGHT FORESIGHT
DE ELEV
STA RR VD RR VD
S(m) θ S(m) θ (m) (m)
(m) (m) (m) (m)
BM1 1.245 -4°25’ 2.42 75.0
TP1 2.044 3°20’ 1.08 1.515 8°18’ 1.55
BM2 1.438 -3°25’ 3.06
Solution:
BACKSIGHT FORESIGHT
DE ELEV
STA RR VD RR VD
S(m) θ S(m) θ (m) (m)
(m) (m) (m) (m)
BM1 1.245 -4°25’ 2.42 -9.56 75.0
TP1 2.044 3°20’ 1.08 11.86 1.515 8°18’ 1.55 21.64 32.07 107.07
BM2 1.438 -3°25’ 3.06 -8.55 -22.39 84.68
Height difference between the two ends of the theodolite ray = 100s
sin0 cos 0, where s = stadia intercept and 6 = V.A.)
V = 100 s sin 6 cos 6
= 50 s sin 2 6
To A, V = 50(6-20 - 3*10) sin 0°04'
= +0-18 ft
Difference in level from instrument axis +0.18
-4.65
-4.47
Check reading
V = 50(3-10) sin0°40'
= +1.80
Difference in level from instrument axis + 1.80
-6.26
-4.46
mean -4.465
To B,
V = 50(10-20 -3-00) sin 0°36'
= -3-76
Difference in level from instrument axis - 3.76
- 6.60
-10.36
Check level -10.37
mean -10.365
Difference in level A - B - 10.365
- 4.465
- 5.900 ft
VI. AREA WITH IRREGULAR BOUNDARIES (BY
TRAPEZOIDAL RULE OR SIMPSON’S RULE)
1.) A series of perpendicular offsets were taken from a transit line to an
irregular boundary. The following offsets were taken at 15 m intervals
from a survey line to an irregular boundary line: 3.50, 4.30, 6.75, 5.25,
7.50, 8.80, 7.90, 6.40, 4.40, and 3.25 m. By the trapezoidal rule and
simpson’s one third rule, find the area included between the transit
line, the curve boundary and the end offsets.
Determining area of an irregular boundary.
8.80 m
9.30 m
hh6
6 7.90 m
7.50 m
6.75 m h5 h7 6.40 m
h3 5.25 m h8
4.30 m h4 4.40 m
3.50 m h2 h9 3.25 m
h1 h10
Solution:
a.) By Trapezoidal Rule:
ℎ1 + ℎ1𝑜
AREA = d ( + h2 + h 3 + h4 + h 5 + h 6 + h 7 + h 8 + h 9 )
2
3.50 + 3.25
AREA = 15 ( + 4.30 + 6.75 + 5.25 + 7.50 + 8.80 + 7.90+
2
6.40 + 4.40)
AREA = 820.125 m2
b.) By Simpson’s One Third Rule:
𝑑 𝑑
AREA = [(h1 + h9) + 2(h3 + h5 + h7) + 4(h2 + h4 + h6 + h8)] +
3 2
(h9 + h10)
15
AREA = [(3.50 + 4.40) + 2(6.75 + 7.50 + 7.90) + 4(4.30 + 5.25
3
15
+ 8.80 + 6.40)] + (4.40 + 3.25)
2
AREA = 813.375 m2
d d d d d d d d
Solution:
a.) Simpson’s One Third Rule:
𝑑
AREA = [h1 + h9 + 2(h3 + h5 + h7) + 4(h2 + h4 + h6 + h8)]
3
4
AREA = [1.50 + 3.30 + 2(3.50 + 9.50 + 4.80) + 4(2.40 + 6.60 +
3
8.40 + 6.10)]
AREA = 179.20 m2
b.) Trapezoidal Rule:
ℎ1 +ℎ9
AREA = d [( ) + h2 + h3 + h4 + h5 + h6 + h7 + h8]
2
1.50 +3.30
AREA = 4 [( ) + 2.40 + 3.50 + 6.60 + 9.50 + 8.40 + 4.80 +
2
6.10]
AREA = 174.80 m2
VII. MISSING SIDES AND/OR BEARING OF CLOSED
TRAVERSE
1.) Given the following descriptions of a four - sided lot.
2A = 7299.81
A = 3649.91 m²
1
SOLUTION:
a.) DMD of line 3-4:
Latitude of (6-1):
Σ Lat = 0
+ 84.60 + 95.32 + 62.66 - 48.16 - 43.04 – y = 0
y = - 151.38
Departure of (1-2):
Σ(Dep) = 0
x - 56.11 - 57.52 - 31.40 + 59.70 + 47.63 = 0
x = 37.70
a.) The lot is to be divided such that the area of the southern portion
would be 210,000m². Compute the position of the other end of the
dividing line, if the line starts at corner 3 of the lot. Express the
distance from corner 1.
b.) What is the length of the dividing line?
c.) Compute the azimuth of the dividing line.
SOLUTION:
a.) Location of x from corner 1
𝑥(960.22)(𝑠𝑖𝑛40°)
210,000 =
2
x = 680.47
680.47 619.67
=
sin 𝜃 sin 40 °
Ɵ = 44” 54’
Bearing = S 44” 54 W
Azimuth = 84” 54’
2.) The following data of a given 4 sided lot.
LINES BEARING DISTANCES (m)
AB N 20” E ?
BC Due East 200
CD S 30” W ?
DA Due West 300
a.) Find the area of the lot in m².
b.) Find the length of the dividing line (EF) that is parallel to line DA
which will divide the lot into two equal areas.
c.) Determine the location of one end of the dividing line E from corner
A along line AB.
SOLUTION
a.) Area of lot:
(300)2 −(200)2
A=
2 ((cot 70 )+cot 58)
A = 25,282.16 m2
c.) Length of dividing line:
√(1)(300)2 +(1)(200)2
x=
1+2
x = 254.95 m
c.) Distance AE:
a = 300 – 254.95
a = 45.05
𝐴𝐸 45.05 AE = 48.48 m
=
sin 58 ° sin 52°