Level:
Project ID:
9000007210
Accepted:
1
Clonable:
0
Easy:
0
Jane has to reach the opposite shore of a lake. She has three possibilities how to
cross. She can use her own boat, start immediately and sail at the velocity
\(4\, \mathrm{km}/\mathrm{h}\). Another option is to wait for her friend, Peter, with a
faster boat. Peter's boat is capable to sail at the velocity
\(10\, \mathrm{km}/\mathrm{h}\).
However, his boat will be available in
\(1.5\)
hours from now. The last option is to use the regular passenger
transportation line which will departure in
\(2.25\) hours
from now and sails at the speed \(20\, \mathrm{km}/\mathrm{h}\). Find the interval of distances to the opposite shore for which the fastest option is to
use Peter's boat.
between \(10\)
and \(15\)
kilometers
up to \(10\)
kilometers
between \(15\)
and \(20\)
kilometers
larger that \(20\)
kilometers