Question

in a biology course, students spend 250 minutes in a lab and lecture each week. the lab time is 20 minutes shorter than the lecture time. let x= the number of minutes the students spend in lecture​

Answer 1

The students spent 135 minutes in lecture and 115 minutes in a lab.

Explanation:

Let x and y be the respective amount of time students spent in lecture and lab.

x-20=y --- eqn 1

x+y=250 --- eqn 2

From eqn 1, x=y+20 --- eqn 3

Sub eqn 3 into eqn 2:

y+20+y=250

2y=230

y=115

Sub y=115 into eqn 3:

x=115+20

=135

∴x=135, y=115