Arron ran a distance of 5km at an average speed of 2.2 m/s - OCR - GCSE Maths - Question 15 - 2019 - Paper 1

For Claudine's average speed, we first calculate the lower and upper bounds for both distance and time:

1. Distance:

   • Lower bound: (53 - 0.5 = 52.5) km
   • Upper bound: (53 + 0.5 = 53.5) km

2. Time:

   • Lower bound: (2.7 - 0.05 = 2.65) hours
   • Upper bound: (2.7 + 0.05 = 2.75) hours

Now, we convert the time into seconds for the calculations:

• Lower bound time in seconds:

$2.65 ext{ hours} = 2.65 imes 3600 = 9540 ext{ seconds}$

• Upper bound time in seconds:

$2.75 ext{ hours} = 2.75 imes 3600 = 9900 ext{ seconds}$

Now we can find the average speeds:

• Lower bound speed:

$\text{Lower bound speed} = \frac{52.5 ext{ km}}{2.75 ext{ hours}} \approx 19.09 \text{ km/h}$

• Upper bound speed:

$\text{Upper bound speed} = \frac{53.5 ext{ km}}{2.65 ext{ hours}} \approx 20.15 \text{ km/h}$

Thus, the lower and upper bounds of Claudine's average speed are approximately 19.09 km/h and 20.15 km/h respectively.