Answer:
Radius = 8.575 cm
Step-by-step explanation:
Formula for volume of a pyramid is;
V_p = ½Ah
Where A is area of base and h is height
Also, formula for volume of cone is given as;
V_c = ⅓πr²h
Now, we are told that V_p = V_c and that h is the same for both shapes.
Thus ;
½Ah = ⅓πr²h
h will cancel out to give;
½A = ⅓πr²
Cross multiply to give;
3A/2π = r²
Base area of pyramid is given as 154 cm². Thus;
(3 × 154)/2π = r²
r = √((3 × 154)/2π
r = 8.575 cm