Cups A and B are cone shaped and have heights of 25 cm25cm and 18 cm18cm and openings with radii of 8 cm8cm and 9 cm9cm, respectively. If cup B is full and its contents are poured into cup A, will cup A overflow? If not how high will cup A be filled?

1 Answer
Jun 22, 2018

The cup will not overflow and 24.2424.24 cm high of cup A will be filled.

Explanation:

Height and radius of cup A is h_a=25 cm , r_a=8ha=25cm,ra=8 cm

Volume of cup A is 1/3*pi*r^2*h :.V_a=1/3*pi*8^2*25 or

V_a~~ 1675.52 cubic cm.

Height and radius of cup B is h_b=18 cm , r_b=9 cm

:.V_b=1/3*pi*9^2*18 or V_b~~ 1526.81 cubic cm

Since V_a > V_b , the content will not overflow.

The ratio of radius and height of cup A is r/h=8/25 .

The ratio of radius and height of content cone in cup A

is r_c/h_c=8/25 or r_c=(8*h_c)/25

The volume of content cone is V_c~~1526.81 cubic cm.

:.1/3*pi*r_c^2*h_c ~~1526.81 or

1/3*pi*((8*h_c)/25)^2*h_c ~~1526.81 or

h_c^3= (1526.81*75)/(8*pi)~~14238.24 or

h_w= root(3)14238.24 ~~ 24.237 (2dp) cm

24.24 cm high of cup A will be filled [Ans]