Answer
P-value $\lt0.001$. Reject the null hypothesis.
There is enough evidence to conclude that Kumon's methods develop mathematical ability.
But maybe, the Kumon selects the best students, so the given results are not due to the Kumon's methods, but to the higher level of Kumon's students.
Work Step by Step
$H_0:~p̂ _1=p̂ _2$ versus $H_1:~p̂ _1\lt p̂ _2$
In MINITAB, select Stat -> Basic Statistics -> 2 Proportions
Select "Summarized data"
For Sample 1 enter 73 in "Number of events" and 400 in "Number of trials".
For Sample 2 enter 130 in "Number of events" and 400 in "Number of trials".
Click in Options. Enter 95 in Confidence level, 0 in Hypothesized difference. In "Alternative hypothesis" select "Difference < hypothesized difference". In "Test method" select "Use the pooled estimate of the proportion". Click OK.
Click OK.
