Q10 of 14 Page 206

The sides of a triangular field are 41m 40m and 9m. Find the number of flower beds that can be prepared in the field if each flower bed needs 900cm2 space.

Given sides of triangular field = 41m, 40m and 9m.


= Total number of flower bed =


We know Area of one flower bed = 900cm2 = 0.09m2





∴ Sides of triangular field are a = 41m, b = 40m, c = 9m.


∴ by Heron’s formula, we get the area of triangle


=


(where s = s is called as the semi perimeter )…(1)


∴ we get


Substituting the value of s, a, b and c in equation 1 we get


⇒


=


=


∴ The area of the triangular field is .


Total number of flower bed =


=


∴ Total number of flower beds that can be placed is 2000.


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