Answer:
x = 31/3
Step-by-step explanation:
4x+8+2x+20=90
4x+2x+8+20=90
4x+2x+8+20=90
6x+28=90
6x+28-28=90-28
6x=62
x = 31/3
Joint Frequency because of the fact that it "joins" one number from the column(up and down) and one from the row(side-by-side), hence the two-way table.
P = IRT
T=P/(IR)
hope helped