Real-Life Math
You are a fisheries officer working on a river that flows from the
ocean up to an important salmon spawning ground. Each year, you and a team
of workers do a count of the salmon running the river.
This is done
to ensure that the number of salmon isn't depleting. "We don't have
to use as much math as an officer working in forestry," says Ari Turunen.
"But we have to have basic math skills for doing things such as calculating
the returns of fish."
In 2001, 12,000 fish returned up the river. In
2002, that figure swelled to 15,000. However, in 2003, only 10,000 salmon
were counted. A number of influences such as overfishing, environmental degradation
and high water temperatures may have led to that figure.
1.) Over the
3 years, what is the average number of fish going upriver?
2.) What
was the percentage decrease in the number of fish going upriver in 2003 compared
to 2002?