Question

The radii of the circular ends of a bucket of height 15cm are 14cm and r cm (r<14cm).
If the volume of bucket is 5390cm, find the value of r.

Answer 1

Answer:

Step-by-step explanation:

volume of the bucket=1/3πh(R²+r²+Rr)

=5390=1/3*22/7*15(196+r²+14r)

=5390=22/7*5(196+r²+14r)

=5390*7/110=196+r²+14r

=49*7=196+r²+14r

=343=196+r²+14r

=0=196-343+r²+14r

=0=r²+14r-147

=r²+21r-7r-147=0

=r(r+21)-7(r+21)=0

=(r-7)(r+21)=0

r=7 or -21(rejected)

hence r=7