“We need a revolution to reverse that silly ratio,” he said.

To that end, the Cooper-Hewitt National Design Museum, which is housed in Andrew Carnegie’s 64-room mansion on Fifth Avenue and offers a $250 red chrome piggy bank in its gift shop, is honoring inventors dedicated to “the other 90 percent,” particularly the billions of people living on less than $2 a day.

Image One computer for every child.

Their creations, on display in the museum garden until Sept. 23, have a sort of forehead-thumping “Why didn’t someone think of that before?” quality.

Image A portable light mat. Credit... Stanford Richins

For example, one of the simplest and yet most elegant designs tackles a job that millions of women and girls spend many hours doing each year — fetching water. Balancing heavy jerry cans on the head may lead to elegant posture, but it is backbreaking work and sometimes causes crippling injuries. The Q-Drum, a circular jerry can, holds 20 gallons, and it rolls smoothly enough for a child to tow it on a rope.