Eco-Fone's two retail shops offer discounted mobile phones and accessories. Both shops have been running for several months and Eco-Fone now wants to compare the net taking from both shops. A sample of 40 net daily takings from the first shop has a mean 100 and a standard deviationof 20. A sample of 40 net daily takings from the second shop has a mean of 90 and a standard deviation of 40.

Are the two shops' net takings the same? Using the 5% level of significance, explain your findings.

Can you please further explain the solution to this? What would be the numerical relations in such a case?