Latest TCS Aptitude Question SOLUTION: From a point within an equilateral triangle, perpendiculars are drawn to the three sides and are 3, 7 and 11 cm in length. Then the perimeter of the triangle (in cm) is a. 42√3

• Placement Papers
• /
• TCS
• /
• Numerical Ability
• /
• Area and Volume

TCS Question Papers: TCS Interview Experience(91) TCS Company Profile

(#M40026168) TCS Numerical Ability question Keep an EYE

From a point within an equilateral triangle, perpendiculars are drawn to the three sides and are 3, 7 and 11 cm in length. Then the perimeter of the triangle (in cm) is

a. 42√3
b. 21√2
c. 21
d. 7

Asked In TCS NITISH KUMAR (11 years ago)

Unsolved Read Solution (4)

Is this Puzzle helpful?   (5)   (0) Submit Your Solution Area and Volume

Read Solution (4) :

Abhisek Das  (11 years ago)

Taking 3 perpendiculars within the triangle from the same point and joining that point to the corners of the triangle, makes three triangles within the equilateral triangle.

Given the sides of the perpendicular as 3cm, 7cm and 11cm.

Let the side of the equilateral triangle be a

Then,

Area of the equilateral triangle = (3^(1/2)*(a^2))/4

So √3a^2/4 = 1/2*3*a + 1/2*7*a + 1/2*11*a
= 1/2(21a)
= 21a/2
=> a = 42/√3
=> 3a = 42*√3

Thus, the perimeter of the triangle is 42√3 cm.

Is this solution Helpfull? Yes (45) | No   

pravin  (11 years ago)

area of equilateral triangle is(root(3)/4)a^2.............................................................(eq1)....and area due to these three triangle formed within the equilateral triangle is ((1/2)*3*a)+((1/2)*7*a)+((1/2)*11*a)..................(eq2)...........equating eq1 and eq2 we get....42/(root(2))

Is this solution Helpfull? Yes (2) | No (4)  

aditya tiwari  (11 years ago)

42..is it correct

Is this solution Helpfull? Yes | No (3)  

yvs radhika  (11 years ago)

area of the eq.triangl=root3/4=x ^2.....eq(1)
the perpendiculars cut the side into two equal parts,therefore area=1/2*3x+1/2*7x+1/2*11x....eq(2)
equalize 1&2..;we get
root3/4*x^2=1/2*3x+1/2*7x+1/2*11x
a=42/root3.
perimeter of the triangle=3x=3*42/root3
=42*root3

Is this solution Helpfull? Yes | No   

Please Login to Read Solution.