1⟩ You are conducting a study looking at the group differences in reading ability between three groups of children, all receiving different remedial assistance. You decide that ages will co vary with reading ability, so you do ANCOVA. There are 40 children in each of the three groups. The mean reading score for the whole sample is 42.69. The mean for group 1 is 46.92, for group 2 the mean is 41.89, and for group 3 the mean is 41.05. What is the grand mean?
1. 3.25
2. 2) 43.29
3. 3) 129.86
4. 4) 42.69
43.29