Ryan mows lawns in the summer. He charges $15 for every 1/2 hour of mowing. This is represented by the equation y = 15x, where y is the total amount Ryan charges and x is the number of 1/2 -hour sessions of mowing. If mr.smith lawn takes 2 hours to mow and mrs.jones lawn 3.5 hours to mow, how much more would Ryan charge mrs Jones then me.smuth