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BrokenToe
04-08-2016, 04:58 PM
​Micheal drove from London to Oxford
The distance from London to Oxford is about 60 miles, correct to the nearest 5 miles
The drive took him 50 minutes, correct to the nearest 5 minutes.
Determine the upper bound for the average speed of the journey. Round your answer to 3 significant figures and give your answer in miles per hour. Thanks.

Ineed Umar
04-08-2016, 05:22 PM
To find upper bound do this. Divide 5 by 2 and you get 2.5.

Upper bound of 60 miles = 62.5.

Now for the lower bound we subtract 5/2 from 50.

Lower bound of 50 minutes = 47.5.

Finally divide miles by hours.

62.5/(47.5÷60) therefore value of speed = 78.948 mph.

Round off to 3 sig = 78.9 mph.

Notice I am about to sleep and I have posted this hurriedly therefore it may be wrong tho.

Make sure you do ur question yourself next time. If you can't, ask your teacher it helps a lot.

BrokenToe
04-09-2016, 12:05 PM
Thanks

M.I.A.
04-09-2016, 03:14 PM
60/50

1.2 miles per min, 1.2 x 60 = 72

72.4 mph

...upper bounds for the average speed.

No speeding plz :p

...although I'm probably wrong T_T

Upper bounds for time to nearest 5 min, 52.29

60/52.29

1.15 miles per min, 69 mph

:/ better but probably still wrong.

T-T

...69.4 mph

Upper bounds are calculated to the nearest .5

69.5 mph ...I forgot to put my name on the paper :/