Which equation could be used to solve this problem?

kate weighs 3 times as much as jen. their total weight is 140 pounds. how much does each girl weigh?
a) 140 = 3x
b) 3x + x = 140
c) 3x - x = 140
d) x - 140 = 3x

How do i do this activity, is appreciated

Empty box + box + empty box fill in the box is equal to 30 how

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?