4. Jason organised a team to set out 728 chairs for a school concert in the school hall. After 5 minutes the team had set out \( \frac{3}{28} \) of the chairs. Calculate: 4.1 how many chairs had been set out after 5 minutes 4.2 what fraction of the chairs had been set out after 45 minutes 4.3 how many chairs had been set out after 45 minutes.

To find out how many chairs had been set out after 5 minutes, we need to calculate \( \frac{3}{28} \) of the total 728 chairs. 4.1 After 5 minutes: \[ \text{Chairs set out} = 728 \times \frac{3}{28} = 78 \] So, after 5 minutes, 78 chairs had been set out. Now, let’s assess the rate of setting chairs to figure out how many chairs would be set out after 45 minutes. 4.2 To establish the fraction of chairs set out after 45 minutes, we need to determine how many sets of 5 minutes fit into 45 minutes. 45 minutes divided by 5 minutes equals 9 sets: In those 9 sets, they set out \( 78 \) chairs in each set, making: \[ \text{Chairs set out after 45 minutes} = 78 \times 9 = 702 \] The fraction of chairs set out after 45 minutes can then be calculated as: \[ \frac{702}{728} = \frac{351}{364} \] So, after 45 minutes, \( \frac{351}{364} \) of the chairs had been set out. 4.3 Finally, we already calculated that the number of chairs set out after 45 minutes is 702 chairs. So, the answer is: **Chairs set out after 45 minutes: 702 chairs**.