A triangle and a parallelogram are constructed on the same base such that their areas are equal. If the altitude of the parallelogram is 100 m , then the altitude of the triangle is

Let the triangle and parallelogram have common base b, 

let the Altitude of triangle is h1 and of parallelogram is h2(which is equal to 100 m), then  

Area of triangle    =  $\frac{1}{2}\times b\times h1$ 

Area of rectangle  = b*h2 

As per Given,

$\frac{1}{2}*b*h1=b*h2$

$\frac{1}{2}*b*h1=b*100$

 h1=200