Answer:
Relative frequency, by row, of students who like both tacos and pizza is:
0.81
Step-by-step explanation:
                                   Like Tacos	Do Not Like Tacos      Total
Like Pizza                    57                	13                       70
Do Not Like Pizza            12                  15                       27
Total                            69          28                       97
The relative frequency by row is calculated as the ratio of the frequency of the required field to the total frequency of that row
Hence, relative frequency, by row, of students who like both tacos and pizza is:
57/70
=0.81