A bag contains blue and green marbles in the ratio of 2 : 5. There is a total of 91 marbles in the bag. How many more blue marbles must be added into the bag so that the number of blue marbles will be the same as the number of green marbles?
The ratio of the number of banana tarts to strawberry tarts is 3 : 5. The ratio of the number of kaya tarts to the total number of banana tarts and strawberry tarts is 5 : 1. What fraction of the tarts are strawberry tarts?