In a room, 57 of the girls wore cardigans. After 86 girls who wore cardigans left the room, the percentage of girls who wore cardigans decreased to 10%. How many girls in the room did not wear cardigans?
There were some pencils in Box A and Box B. After Carl transferred 34 of the pencils from Box A to Box B, the ratio of the number of pencils in Box A to that in Box B changed to 2 : 9. Find the ratio of the numbers of pencils in Box A to the number of pencils in Box B at first.
At a stall, the ratio of watermelons to coconuts was 8 : 13. After Kate bought two-thirds of the coconuts, there was a total of 111 watermelons and coconuts left at the stall. How many fruits were there at first?