Question

a triangular feild has the demesions 40 m, 30 m, 20 m long respectively. find the length of fencing that goes round it 3 times.

Answer 1

Step-by-step explanation:

Dimension of triangle field ⇒120m,80m,50m

⇒ perimeter = 120 + 80 + 50

=250m

Area =

125(125−120)(125−80)125−50

=

125×5×45×75

=

25×5×5×9×5×5×15

=5×5×3×5

15

=375

15

=375(3.88)

=1455m

2

cost of fencing = 250−3

[perimeter of Remaining fence] = 247

Total cost ⇒247m×Rs20/m

=Rs4940.

as the rate are reduced by 25 %

∴ new lets is [20−20×

100

25

]⇒20−5=15%

Rs[4950−4950×

100

25

]

⇒4950(1−

4

1

)

4950×

4

3

Final cost ⇒Rs3712.5

Answer 2

3× perimeter of triangle

Step-by-step explanation:

as explained above

perimeter of the triangle= (40+30+20)m =90m

hence, the length of fencing that goes three round around it = 3×90

= 270m.

hope, it will help you ;)