9.03 Comparative inferences
Interactive practice questions
Judy thinks there may be a difference in the way males and females compute certain puzzles. She gave an equal number of boys and girls a knot to undo and recorded how long (in seconds) it took each of them. The results are presented in the table:
| Boys | $32$32 | $38$38 | $39$39 | $37$37 | $33$33 | $37$37 | $39$39 | $38$38 | $39$39 |
|---|---|---|---|---|---|---|---|---|---|
| Girls | $34$34 | $37$37 | $44$44 | $37$37 | $41$41 | $46$46 | $28$28 | $42$42 | $46$46 |
Judging by observation, which group took longer on average to undo the knot?
Girls
Boys
What was the quickest time anyone took to untie the knot?
Judy thinks that since the boys have the least mean, they are likely to be better at such a puzzle.
Robert thinks that since a girl was the quickest in untying the knot, this means girls are more likely to be better at such a puzzle.
Statistically, who has the stronger claim?
Robert
Judy
The following box-and-whisker plot shows the number of points scored by two basketball teams in each of their matches last season.
The following column graphs show the season results of two soccer groups, Group A and Group B, and the number of games (frequency) in which they scored a certain number of goals (scores).
The box plots drawn below show the number of repetitions of a $70$70 kg bar that two weightlifters can lift. They both record their repetitions over $30$30 days.