Thống kê năng suất một loại cây trồng (Y: tấn/ha) và lượng đầu tư cho cải tạo đất (X: triệu đồng/ha) tại tỉnh A trong một số năm ta được bảng sau:

xi	20	23	25	28	30
yi	2	3	5	6	8

Hệ số tương quan mẫu giữa năng suất cây trồng loại này và lượng đầu tư cải tạo đất là:

Chia sẻ

Một số câu hỏi khác có thể bạn quan tâm.

• Choose the correct sentence which is built from the words and phrases given:

  I / let/ borrow/ novel/ but/ you/ promise/ return/ next week.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  Title Mrs./ indicate/ married/ while/ Miss/ unmarried one.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  If I / not/ television/I / heard/ burglar alarm/ off.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  I / not/ her temperature yet/ but/ face/ flushed/ seem/ feverish.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  I / down/ stairs and/ lucky/ get away/ few bruises.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  He/ suffers/ rare tropical disease/ which/ contracted/ while/ Africa.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  She/ gave/ nursing training/ when/ found/ no vocation/ looking after/ sick.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  I / visit/ girl/ make/ friends/ hostel.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  It/ rain/ manager/ get/ office/ morning.
  
  

• Choose the correct sentence which is built from the words and phrases given:

  When/ boy/ twelve/ father/ die/ dangerous disease.