Old Faithful

Old Faithful, a famous geyser in Yellowstone National Park, erupts approximately once every 77 minutes. (It used to erupt more frequently, but earthquakes have changed the geyser’s plumbing, so it’s not letting off a little steam as often as it used to.) Assuming that it spurts 8000 gallons of water each time, how many gallons will Old Faithful spurt in one year?

The Fourth of July

When most of us think of the Fourth of July, we think of fireworks!  Over the years, fireworks have become more and more elaborate.  However, this is also the time of year when safety agencies are concerned about the improper use of fireworks and the possible injuries that can occur.  Fireworks are safer now than they used to be but can still cause very serious injuries. In 1990, there were 17.8 injuries per 100,000 pounds of fireworks.

On the Road Again

Each summer Radolpho, Lucia and Mya, along with their families, spend two weeks on vacation at their shared lake house.

Mya travels the furthest distance to get to the lake house from her home. Mya’s truck has a fuel tank that holds 12 gallons of gas, and she can drive an average of 22 miles per gallon of gas. If Mya leaves home with a full tank of gas, drives directly to the lake house, and arrives with exactly 1/8 tank of gas remaining, how far does Mya travel from her home to the lake house?

The Unofficial Start of Summer

Memorial Day has always been the unofficial start of summer. Here are some problems about some things we love in hot weather!

Two local supermarkets sell watermelons grown at McDowell’s farm. But Biggy Market sells their watermelons for $3.99 each, regardless of size, whereas Harmless Trail Market sells their watermelons for $0.19 per pound.  For what weight will a watermelon at Harmless Trail cost the same as any watermelon at Biggy? If the largest watermelon grown at McDowell’s farm weighs 18 pounds, at which place should you buy your watermelons?

Spring Growth

A 6-inch tall flower casts a 4-inch shadow at 5:00pm. One month later, when the sun was at the same position in the sky as it was at 5:00pm one month earlier, the shadow cast was 5 1/3 inches long.

St. Patrick's Day

Riley sees a rainbow with ends that appear to touch the ground 1 mile apart and reaches a maximum height of 0.5 miles above the ground. If the rainbow is an arc of a circle, how many degrees is the arc that Riley sees?

First, let's draw a diagram: 

Valentine's Day Treats

According to “A History of Valentine’s Day Cards in America” by T.M. Wilson, in 1847 Esther Howland was the first to mass-produce Valentine’s Day cards.  She made them out of lace, paint and expensive paper and each one was individually written by a skilled calligrapher.  The average card sold for $7.50 while others cost as much as $50.  If 10 cents in 1847 would be equivalent to $1.85 today, how much would the average card and most expensive card have cost today?

E-Week 2020: Biomedical Engineering


Today's Problem: Biomedical Engineering

Biomedical engineers play a vital role in medical advances and innovations that improve our health and save lives. One application of their work is advancing research into specialized care for patients. This set of problems looks at a recent biomedical invention—artificial hearts for people who suffer from certain forms of heart disease.