A large shipment of produce contains Valencia and navel oranges. To determine whether there is a difference in the proportions of non-marketable fruit between the two varieties, random samples of 850 Valencia oranges and 1,500 navel oranges are independently selected and the number of non-marketable oranges of each type is counted. It is found that 30 Valencia and 90 navel oranges from these samples are non-marketable. Do these data provide sufficient evidence to indicate a difference between the proportions of non-marketable Valencia and navel oranges? Test at the 5% level of significance