After 10 seconds, the bacteria split into 1 strong and 1 weak bacteria, and 1 weak bacteria split twice in 50 seconds, and one * * * became four weak bacteria. The divided strong bacteria split at 20 o'clock and became 1 strong bacteria and 1 weak bacteria. This weak bacteria can divide twice again and become four weak bacteria. The strong bacteria that divide again divide in 30 seconds, and the weak bacteria that divide in 40 seconds can only divide once, each producing two weak bacteria. The weak bacteria that divide in 50 seconds and 60 seconds have no chance to divide. Finally, the number of bacteria in * * * = 1 (strong bacteria)+1 (weak bacteria)+1 (weak bacteria) +2 (weak bacteria) +4 (weak bacteria).