The cost of one dozen bananas is Rs. 5. The cost of one dozen oranges is Rs. 75. What will the cost of one and a quarter dozen bananas and three-fourth dozen oranges?

given 

cost of 12 banana = 5 

so therefore cost of one banana is $$\frac{5}{12}$$

we also know 1 dozen = 12 

therefore quarter dozen ($$\frac{1}{4}$$) is 3 fruits

similarly $$\frac{3}{4}$$ dozen is 9 fruits

so cost of one and a quarter dozen banana i.e 12 + 3 = 15 banana is $$\frac{5}{12}\times{15}$$

                                                                                       = 6.25 rs

similarly cost of 12 oranges = 75 rs

therefore cost of one orange is $$\frac{75}{12}$$

therefore cost of 9 oranges is $$\frac{75}{12}\times{9}$$

                                                =  56.25

hence total cost of fruits are 6.25 + 56.25

                                             =62.5 rs

making option D as the correct answer