A train travels 150 km in the same time that a plane travels 400 km. if the rate of the plane is 20 km per hour less than three times the rate of the train, find both rates

Speed of train =  60 km/hr

Speed of plane = 160 km/hr

Explanation:

We can construct the following equations from the given information:

Speed of train * time = 150                                              -Equation 1

Speed of plane * time = 400                                           -Equation 2

Speed of plane = (3 * Speed of train) - 20                      -Equation 3

We can solve these three simultaneous equations for the three variables (speed of train , speed of plane, time).

Substituting within Eq. 1 and Eq. 2 we get:

Speed of plane * 150 = 400 * Speed of train   -Equation 4

Finally, solving Eq. 4 and Eq. 3 simultaneously we get:

Speed of train =  60 km/hr

Speed of plane = 160 km/hr

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).