1: The number of boys in a class is four fifths of that of girls. What is the ratio of girls to boys? 2. A project is completed by team A alone 1 1 day, and teams A and B complete this project every day. What is the ratio? 3: The ratio of A to C is 7: 4, and A minus 24 equals B. What were the original numbers of A and B? The average of 4:A, B and C is 75. Given that A, B and C are 4: 5 and 2: 3 respectively, what are they? 5. The proportion of students in the fourth, fifth and sixth grades in bright primary school is11:14:12, and the average of each grade is11. How many students are there in each of the three grades 6. The ratio of students in Class One to Class Two is 7: 5. The two classes plant trees together. The saplings are distributed according to the number of students. As a result, there are six more trees in class one. How many seedlings are there in each class? 7. Both parties read a book at the same time. Party A has read a third of the books, and there are 352 pages left. When Party A finished reading, Party B only read four fifths of the books. How many pages are there in this book? 8. When two students, A and B, come home from school, A has to walk 65,438+0 more than B, and B has to walk 65,438+065,438+0 less than A. The speed ratio of A and B is 9: It takes 6 minutes for A to manufacture a part, 5 minutes for B and 4.5 minutes 10.