GCSE Secondary Maths Age 13-17 - Number: Upper and Lower Bounds - Explained

The video tutorial explains how to determine if a train's average speed could exceed 160 km/h using upper and lower bounds for distance and time. It covers calculating these bounds, determining maximum speed, and the impact of measurement assumptions. The tutorial concludes that the maximum speed is 153.49 km/h, thus not exceeding 160 km/h. It also discusses how changing the rounding of the track's measurement affects the speed calculation.

What assumption did Jake make about the track's measurement?

• It was measured to the nearest 1 kilometer.

• It was measured to the nearest 5 kilometers.

• It was measured to the nearest 100 kilometers.

• It was measured to the nearest 10 kilometers.

How is the upper bound of the distance determined?

• By adding 10 to the measured distance.

• By subtracting 10 from the measured distance.

• By subtracting 5 from the measured distance.

• By adding 5 to the measured distance.

What is the formula used to calculate speed in this context?

• Speed = Time x Distance

• Speed = Distance / Time

• Speed = Distance x Time

• Speed = Time / Distance

Why can't the average speed exceed 160 km/h?

• Because the speed limit is 153.49 km/h.

• Because the average calculated speed is 153.49 km/h.

• Because the minimum calculated speed is 153.49 km/h.

• Because the maximum calculated speed is 153.49 km/h.

What was the error in Jake's assumption about the track measurement?

• The track was measured to the nearest 100 kilometers.

• The track was measured to the nearest 1 kilometer.

• The track was measured to the nearest 5 kilometers.

• The track was measured to the nearest 10 kilometers.

How does the correct measurement of the track affect the maximum speed?

• It doubles the maximum speed.

• It has no effect on the maximum speed.

• It decreases the maximum speed.

• It increases the maximum speed.

What is the new upper bound of the distance when measured to the nearest 5 kilometers?

• 265 kilometers

• 272.5 kilometers

• 275 kilometers

• 270 kilometers