Answer:
1/4
Step-by-step explanation:
1/2 - 1/4
2/4 - 1/4 = 1/4
Answer:

Step-by-step explanation:
The mean is the sum of the weights divided by the number of weighings.

Answer:
V = D/t = 10 / 20 = 0.5 mile per min
V = D/t = 20/30 = (2/3) mile per min
V = D/t = (10+20)/ 50 = (3/5) mile per min