Question

J.C. Nichols department store reports that the average sales on Saturdays is twice that on Thursdays and the average sales on Thursdays is twice that on the other four days.What fraction of the weekly sales are made on Thursdays?

a. 1/7
b. 1/5
c. 2/7
d. 1/3
e. 2/5

please answer and explain

Answer 1

Thu sales = $X
Sat sales = $2X
Other 4 days = $X/2

X/(x+2X+X/2) = X/(3 1/2)x = X/(7x/2) =
x * 2/7x = 2/7.