Help help help! I would like some help with this :) given the quadrilateral is a parallelogram, write an equation to find the value of x please :) also solve the question! ​

Shannon mary and john earn a weekly allowance ahannon earns the amount that is 2/3 of what john earns mary earns an amount that is 1 2/3 of what johns earns 20 dollars a week who eaens the greatest allowance and who earns the least