"Thirty women were examined in a hospital by a doctor and the number of   heart
Channel: Doubtnut
Date: 2020-06-28

"Thirty women were examined in a hospital by a doctor and the number of
 
  heart beats per minute recorded and summarised as follows. Find the mean
 
  heart beats per minute for these women, choosing a suitable method.
 No. of heatÂ Â Â Â 65-68Â Â 68-71Â Â 
 
  71-74Â Â 74-77Â Â 77-80Â Â 
 
  80-83Â Â 83-86
 beats 
 (per min.)
 No. of women:Â 2Â Â Â Â Â Â Â Â Â Â 
 
  4Â Â Â Â Â Â Â Â Â 3Â Â Â Â Â Â Â Â Â Â 8Â Â Â Â Â Â Â Â 7Â Â Â Â Â Â Â Â Â Â Â 4Â Â Â Â Â Â Â Â Â 2"