Expert: Josh - 10/8/2007

Question
Help with inequalities! Here it goes: The amount of snow on the ground increased by 8 in. between 7 pm and 10 pm., there was less than 2 ft of snow. how much snow was there by 7 pm.?
Write an inequality to solve each question!
HELP walk me through it please!!

Answer
Briahna,

The information might be incomplete. All we know is a net increase in snow of 8 inches in the 3 hour period between 7pm and 10pm. If it increases uniformly, we can let "m" the rate be 8/3 [in/hr].

The part where it says "there was less than 2 ft of snow" is unclear. When does this observation refer to? Not knowing the starting point, we can't go far.

If we know how much slow there is at time t0, and write this as S(t0), then the amount of snow may be described by a linear model, something like S(t) = S(to)+(8/3)*(t-t0).

For this situation, if we want the amount at time t to be less than 24 inches, we can set this up as S(t0)+(8/3)*(t-t0) < 24. Knowing S(t0), we can work out how much snow at any other time instant. Here, t-t0, is the elapsed time since observation had taken place at t0.

That's the general idea.