A randomized controlled trial is run to evaluate the effectiveness of a new drug for asthma in children. A total of 250 children are randomized to either the new drug or placebo (125 per group). The mean age of children assigned to the new drug is 12.4 with a standard deviation of 3.6 years.  The mean age of children assigned to the placebo is 13.1 with a standard deviation of 4.0 years.  Is there a statistically significant difference in ages of children assigned to the treatments?  Run the appropriate test at a 5% level of significance. Please use the five steps and explain the meaning of the results.

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