12. A freight train left Albany for New York at 6 o'clock. An express left on the same track at 8 o'clock. It went at the rate of 40 miles an hour. At what time of day will it overtake the freight train if the freight train stops after it has gone 56 miles?"
The criteria he had in mind in selecting the problems were as follows:—
"The main purpose of the reasoning test is the determination of the ability of VI A children to reason in arithmetic. To this end, the problems, as selected and arranged, are meant to embody the following conditions:—
1. Situations equally concrete to all VI A children.
2. Graduated difficulties.
a. As to arithmetical thinking.
b. As to familiarity with the situation presented.
3. The omission of
a. Large numbers.
b. Particular memory requirements.
c. Catch problems.
d. All subject matter except whole numbers, fractions, and United States money.
The test is purposely so long that only very rarely did any pupil fully complete it in the fifteen minute limit."
Credits were given of 1, for each of the first five problems, 1.4, 1.2, and 1.6 respectively for problems 6, 7, and 8, and of 2 for each of the others.
Courtis sought to improve the Stone test of problem-solving, replacing it by the two tests reproduced below.