Elitmus Exam Numerical Ability Geometry

Two regular polygons have the number of their sides in the ratio 2:1 and their interior angle in the ratio 5:4. The number of sides of the two polygons are?

Read Solution (Total 3)

let no. of sides of two polygon be 2n & n

since,interior angles of a polygon of n sides is given by (n-2)* 180/n

so [(2n-2)* 180/2n]/[(n-2)* 180/n]= 5/4
=> (n-1)/(n-2)= 5/4
=> n=6
n=6 & 2n=12

so, number of sides of the two polygons are = 12 & 6
10 years agoHelpfull: Yes(74) No(0)

i think interior angles having side n =(n-2)* 180
why are u diving it by extra n @rakesh?
9 years agoHelpfull: Yes(3) No(6)
@ Rohit Bisht .. your formula is for the total sum of interior angles. But we need each angle of the polygon that's why we have to divide by n.
2 years agoHelpfull: Yes(0) No(0)

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