I got a question for you: It is a gentle and intelligent breed whose combination of long, powerful legs, deep chest, flexible spine and slim build allows it to reach average race speeds exceeding 64 kilometres per hour (40 mph). The Greyhound can reach a full speed of 70 kilometres per hour (43 mph) within 30 metres (98 ft), or six strides from the boxes, traveling at almost 20 metres per second (66 ft / s) for the first 250 metres (820 ft) of a race.

Answer this question: how fast can a greyhound run in mph?
Let's think first:
To answer the above question, the relevant sentence is: The Greyhound can reach a full speed of 70 kilometres per hour (43 mph) within 30 metres (98 ft), or six strides from the boxes, traveling at almost 20 metres per second (66 ft / s) for the first 250 metres (820 ft) of a race.
Therefore, the answer is 43.