Null Hypothesis : The true mean height of children is more than 60 inches.
Step-by-step explanation: Null Hypothesis is defined as a hypothesis that there is no significant difference between the observed and sampled mean.
So, if alternative hypothesis is " the true mean height of children is less than 60 inches" which denotes there is significant difference between sampled and observed mean heights so null hypothesis is taken as " true mean height of children is more than 60 inches"
