Let the sides of the triangle be 12k, 17k and 25 k cm.
Then,
Perimeter = 12k+ 17k + 25k = 54k
According to the question,
54k = 540
k = 10
a = 12k = 12 x 10 = 120 cm
b = 17k = 17 x 10 = 170 cm
c = 25k = 25 x 10 = 250 cm
a =122 m
b = 22 m
c = 120 m
1 year =12 months
V Rent for 12 months per m2= र 5000
Rent for 1 month per m2 = र
Rent for 3 months of 1320 m2
Rent for 3 months of 1320 m2
= र (1250 x 1320)
= र 1650000.
a = 15 m
b = 11 m
c = 6 m
Area painted in colour
a = 18 cm
b = 10 cm Perimeter - 42 cm
⇒ a + b + c = 42
⇒ 18 + 10 + c = 42
⇒ 28 + c = 42
⇒ c = 42 – 28
⇒ c = 14 cm
Area of the triangle
A traffic signal board, indicating ‘SCHOOL AHEAD’, is an equilateral triangle with side ‘a’. Find the area of the signal board, using Heron’s formula. If its perimeter is 180 cm, what will be the area of the signal board?
'a' = a
'b' = a
'c' = a
Area of the signal board
Perimeter = 180 cm
'a' + 'b' + 'c' = 180
a + a + a = 180
3a = 180
a = 60 cm
Area of the signal board 
Alternatively,
Area of the signal board
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