Find the area of an equilateral triangle whose side is 3.1 cm. 

Correct option is D

Given:

Side of the equilateral triangle (s) = 3.1 cm

Formula Used:

Area of an equilateral triangle $$= \frac{\sqrt{3}}{4} \times s^2$$​​

Solution:
Substituting the value of s = 3.1 cm into the formula:

Area=$$\frac{\sqrt{3}}{4} \times (3.1)^2$$​

$$\text{Area} = \frac{\sqrt{3}}{4} \times 9.61 = 2.4025\sqrt3$$​

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