| Question 1 |
| Mean | 0 | Standard deviation=1 | | 1 |
| P( | -1.93 | > | X | < | 2.37 | ) |
| | Z1= (x-mean)/std= | | -1.93 |
| | Z2= | 2.37 |
| | P(Z1<-1.93)= | | 0.0268 |
| | P(Z2<2.37)= | | 0.99086 |
| | P(-1.93>X<2.37)= | | 0.96406 |
| Question 2 |
| | xi= 63.8, std = 2.6 |
| | Mean = | 64 |
| | Z=(xi-Mean)/std = (63.8-64)/2.6 = -0.07692 |
| | P(Z<-0.07692) = 0.5-0.02790= 0.4721 |
| | P(Z<63.8) = 0.4721 |
| Question 3 |
| | Mean =69.4 |
| | Std = 11.3 |
| | Xi =66 |
| | Z = (Xi-Mean) / std = (66-69.4)/11.3 = -0.30088 |
| Question 4 |
| | Z = -1.645 |
| | P(Z<1.645) = 0.95 |
| | P(Z< -1.645)= 1-0.95 = 0.05 |
| | P(Z>-1.645) = 1-P(Z<-1.645) = 1-0.05 = 0.95 |
| Question 5 |
| | std= | 0.898 |
| | Z(0.8980)= Z(0.8+0.0980) = 0.31327 |
| | Z(X>0.8980) |
| | 0.5-0.31327 = 0.18673 |
| Question 6 |
| | Min Xi =22, Max= 60 |
| | Mean = 18.2, std = 2.09 |
| | Z=(xi-Mean)/std |
| | Z = (22-18.2)/2.09= 1.1818 |
| | P(X>22) = 1-1.1818= -0.1818 |
| | Table value | | 0.791 | equals | 79.10% |
Gladiola
Workedexcel21.xlsx
