tailieunhanh - sat virtual reality ii explanations phần 3

Tham khảo tài liệu 'sat virtual reality ii explanations phần 3', ngoại ngữ, ngữ pháp tiếng anh phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 4 4 . J . So put in your grid. And even though is the same as 1 don t be tempted to 3 3 3 put 1 - 3 SAT Virtual Reality II 25 into the grid since you can t grid in mixed numbers 22. 9 984 If the ratio of students to teachers to parents is 11 2 3 then there might be 11 students 2 teachers and 3 parents for a total of 16 people. On the other hand there might be 10 X 11 or 110 students 10 X 2 or 20 teachers and 10 X 3 or 30 parents for a total of 10 X 16 or 160 people. In fact there could be any number of people at all as long as they are there in the ratio 11 2 3. That means that the number of people in attendance must be a multiple of 11 2 3 or 16. So what this question is really asking is - what s the greatest multiple of 16 that fits on the grid Since the grid only has 4 columns the largest multiple of 16 that fits will be a 4-digit number in other words a number greater than 999 but less than 10 000. So you need the largest multiple of 16 that is less than 10 000. The easiest way to find that number is to use your calculator and your knowledge of arithmetic. First of all 10 000 16 625 so 10 000 is a multiple of 16. Therefore the largest multiple of 16 that the grid can accomodate must be 10 000 - 16 9 984. You can check that 624 X 16 9 984 on your calculator but you don t have to. 23. 75 Since we re starting off with a group of 10 numbers and then removing 2 of them the highest and the lowest let s express the sum of the 10 numbers as the sum of the highest number the lowest number and the other 8 numbers. The sum of the 10 numbers is equal to the highest number the lowest number the sum of the other 8 numbers. If we call the highest number h the lowest number and the sum of the other 8 numbers S we can express the sum of the 10 numbers as h S. Then the average of the 10 numbers is h 10 S which we re given is S 87. The average of the eight numbers is just and we re given that that s 90. We 8 h want to know the average of the 2 grades that were removed or 2 If I .