Statistics
posted by Maria Elizabeth .
A number of grade school students were asked about their perceived math ability and the results are in the table below.
Below Average = BA
Average = A
Above Average = AV
BA A AV
Girls 61 54 21
Boys 43 61 42
Test at the 0.01 level if there is a difference between girls and boys with respect to their perceived math ability.

Use the Chisquare (X^2) method.
X^2 = ∑ (OE)^2/E, where O = observed frequency and E = expected frequency.
∑ = sum of all the cells.
E = (column total * row total)/grand total
df = n  1, where n = number of cells
Look up value in X^2 table in the back of your textbook.