Page 63 - WCS - Electrical

130
20
50 +
60 +
=
=
2
= 65 cm
= sx

a)
(s −

b)
(s −

(s −
c) unit
Area A

-
60)(65
50)(65
65(65
-
=

= 65
15
x
45
x
5
x
6 Find the area of an equilateral triangle whose side is
= 468.4 cm
2
5 cm.

3
= 936.8 cm
a unit
=
Area
4
Cost of polish per 100 cm
= Rs. 1.35
2
1.732 2 2 Area of polish on both sides = 2 x 468.4 - 2 2 20) 2
= x 5 x 5 936.8
4 ∴ Cost of polish is 936.8 cm 2 = x 1.35
WORKSHOP CALCULATION & SCIENCE - CITS 2 100
= 10.825 cm
= Rs. 12.65
7 Calculate its perimeter if one side of an equilateral 10 Find the area of the right angled triangle with base 20
triangle is 55 mm long.
7 Calculate its perimeter if one side of an equilateral triangle is 55 mm long. cm and height 8 cm.
Side = 55 mm Base b = 20 cm
Side = 55 mm
Perimeter (P) = ? Equal sides or
Perimeter (P) = ?
P = 3a unit slant height = 8 cm
P = 3a unit
= 3 x 55 Area (A) = ?
= 3 x 55
= 165 mm 1
= 165 mm Area (A) = x base x height unit 2
8 Find the area of the triangle having its sides are 9cm,
8 Find sthe area of the triangle having its sides are 9cm, 10cm and 12 cm. 2
10cm and 12 cm. a b + c + 1
Semi Perimeter = a + c unit = x 20 x 8
2
Semi Perimeter = 2 b + unit 2
9 + 10 2 + 12 31 = 80 cm
= =
2
31
9 + 10 + 12 2 11 Find the area of the right angled triangle if the sides
= = containing the right angle being 10.5 cm and 8.2 cm.
= 15.5 cm 2
2
= 15.5 cm 1
Area A = S(S − a)(S − b)(S − c) unit² Area (A) = x base x height unit 2
2
Area A = sx (s − a) (s − b) (s − c) unit 2
= 15.5(15.5 − 9)(15.5 − 10)(15.5 − 3.5) 1

= 15.5(15.5 - 9)(15.5 - 10)(15.5 - 12) = x 10.5 x 8.2
2
= 15.5 x 6.5 x 5.5 x 3.5 = 43.05 cm 2
= 15.5x 6.5 x 5.5 x 3.5
= 1939.4375 12 Calculate the perpendicular height of the triangle if the
= 1939.4375 area of the right angled triangle is 19.44 m and its one
2
of the adjacent side containing the right angle being
= 44.03 cm
= 44.03 cm² 2 5.4 m.
9 Find the cost of polishing on both sides of a triangular
9 Find the cost of polishing on both sides of a triangular metal plate has sides 60 cm, 50 cm and 20 cm at the
1
rate of Rs.1.35 per 100 cm² metal plate has sides 60 cm, 50 cm and 20 cm at the x base x height unit 2 = Area
rate of Rs.1.35 per 100 cm 2 2
1
a + b + c x 5.4 x h = 19.44
Semi Perimeter = unit 2
2
50 +
60 +
20ireman : (NSQF - Revised 2022) - 1 Year : Exercise 1.7.25
62 WCS - Electrician & W 130 st
= =
2 2
= 65 cm
Area A = sx (s − a) (s − b) (s − c) unit 2

= 65(65 - 60)(65 - 50)(65 - 20)

= 65 x 5 x 15 x 45
6 Find the area of an equilateral triangle whose side is = 468.4 cm 2
5 cm.
3 Area of polish on both sides = 2 x 468.4
Area = a unit 2 = 936.8 cm 2
2
4
Cost of polish per 100 cm 2 = Rs. 1.35
1.732
= x 5 x 5 936.8
4 ∴ Cost of polish is 936.8 cm 2 = x 1.35
100
= 10.825 cm 2
= Rs. 12.65
7 Calculate its perimeter if one side of an equilateral 10 Find the area of the right angled triangle with base 20
50
triangle is 55 mm long. cm and height 8 cm.
Side = 55 mm CITS : WCS - Electrical - Exercise 5
Base b
= 20 cm
Perimeter (P) = ? Equal sides or
P = 3a unit slant height = 8 cm
= 3 x 55 Area (A) = ?
= 165 mm 1
Area (A) = x base x height unit 2
8 Find the area of the triangle having its sides are 9cm, 2
10cm and 12 cm. 1
= x 20 x 8
a + b + c 2
Semi Perimeter = unit 2
2 = 80 cm
9 + 10 + 12 31 11 Find the area of the right angled triangle if the sides
= = containing the right angle being 10.5 cm and 8.2 cm.
2 2
= 15.5 cm 1
Area (A) = x base x height unit 2
Area A = sx (s − a) (s − b) (s − c) unit 2 2
1

= 15.5(15.5 - 9)(15.5 - 10)(15.5 - 12) = x 10.5 x 8.2
2
= 15.5x 6.5 x 5.5 x 3.5 = 43.05 cm 2
12 Calculate the perpendicular height of the triangle if the
= 1939.4375 area of the right angled triangle is 19.44 m and its one
2
of the adjacent side containing the right angle being
= 44.03 cm 2 5.4 m.
9 Find the cost of polishing on both sides of a triangular 1
metal plate has sides 60 cm, 50 cm and 20 cm at the x base x height unit 2 = Area
rate of Rs.1.35 per 100 cm 2 2
1
a + b + c x 5.4 x h = 19.44
Semi Perimeter = unit 2
2
st
62 WCS - Electrician & Wireman : (NSQF - Revised 2022) - 1 Year : Exercise 1.7.25