Word problem

Question

The formula V= √ 2.6r models the maximum safe speed, v, in miles per hour, at which a car can travel on a curved road with radius of curvature r, in feet. A highway crew measures the radius of curvature at an exit ramp on a highway as 510 feet. What is the maximum safe speed? For this problem, round your answer DOWN to the nearest whole number. (Think: Why is this type of rounding appropriate for this scenario?) max safe speed =

Answer 1

I assume you mean 

 

v = √(2.6r).

 

[Please use parentheses.]

 

v_max = √[2.6(510)] mph ≅ 36.4 mph ≅ 36 mph

 

You should always round down to the nearest integer, never up, to ensure margin in the speed.  It is wise to be conservative when estimating maximum safe levels of anything.