Homework Help: Algebra

Posted by Brittany on Thursday, September 22, 2011 at 8:30pm.

A runner wants to run 11.6 km. She knows that her running pace is 8.1 miles per hour. How many minutes must she run?

Algebra - Steve, Friday, September 23, 2011 at 1:47pm
speed = dist/time (as in miles/hr)
The sneaky part here is that everything is in different units. You want to end up with minutes. So, convert everything to miles and minutes

11.6 km * mi/1.6km = 7.2 mi

so, plug and chug:
speed = dist/time
8.1 = 7.2/t
t = 8/9 hr

But we want minutes = 66*8/9 = 53 1/3 min.
Algebra - Steve, Friday, September 23, 2011 at 1:48pm
oops, that's 60*8/9

Related Questions

math - 11. Runner A crosses the starting line of a marathon and runs at an ...
Physics - Runner A is initially 6.0 km west of a flagpole and is running with a ...
Physics - Runner A is running at a constant rate of 2.3 m/s when he passes ...
Math - Runner A crosses the starting line of a marathon and runs at an average ...
physics - Runner A is running at a constant rate of 2.3 m/s when he passes ...
physics - two runners who live 10 miles apart leave home and start running ...
math - Irena is training for an upcoming triathlon and plans to run 12 miles ...
Math - TRIATHLONS Irena is training for an upcoming triathlon and plans to run ...
math - one runner runs 4.75 miles in one hour and runner 2 runs 4 miles in one ...
Math - This is the question. In 1991, an American, Ann Trason, set a world ...

For Further Reading

First Name:
School Subject:
Answer: