Dr. Steve Walks

Why this post? There are three main parts to solving word problems:

1) change the words into math
2) What are they asking for? Look for the question mark! In Minnesota State tests, there can be only one question mark per problem. Not true for this blog. There may be several question marks.
3) Watch out for units! In this problem, distances are in miles but times are in minutes and seconds, and the answer is supposed to be in miles per hour.

The theme of this post is: watch out for units.

The fact that the answers are in miles per hour tells you how to do the problem."Per" means divided by, so the answers are distances in miles divided by times in (fractional) hours. You do have to convert minutes and seconds into fractions of hours or decimal hours.

In later posts, I will try to list all the English words and their math equivalents. For now, "per" always means "divide."

On Tuesday July 1 I walked the first mile in 19 minutes and 20 seconds, and the second mile in 17 minutes and 37 seconds. The total time for two miles was 36 minutes and 57 seconds, and for 2.2 miles, 39 minutes and 4 seconds.

What were my speeds, in miles per hour, for the first mile, the second mile, two miles, and 2.2 miles? (4 answers; round to 2 decimal places.)

On Thursday July 3rd I walked for about 3 miles around the Seward neighborhood with my daughter. She is the mother of my two older grandchildren, who started at Seward Elementary and are now both college graduates and have jobs!

Today, the 4th of July,  I walked the first mile in 19 minutes and 24 seconds, and the second mile in 17 minutes and 37 seconds. The total time for two miles was 37 minutes and 1 second, and for 2.2 miles, 39 minutes and 13 seconds.

Again, what were my speeds, in miles per hour, for the first mile, the second mile, two miles, and 2.2 miles? (4 answers; round to 2 decimal places.)

For example calculations, see the post of June 26 2014. It seems that (usually) first mile is slow, the second mile is faster, two miles is medium fast, and 2.2 miles is faster. The last 2 tenths of a mile are on the flat, and maybe I speed up when the end is in sight. Or, there may be errors in the mile measurements, but I think the 2.2 miles for the whole course is pretty accurate.

Answers in Rot13 -- somewhere on this blog are instructions to decode Rot13:

Whar 1: Svefg zvyr, guerr cbvag bar mreb zcu, frpbaq zvyr guerr cbvag sbhe bar zcu, gjb zvyrf, guerr cbvag gjb svir zcu, gjb cbvag gjb zvyrf, guerr cbvag guerr rvtug zcu.

Whyl 4: Svefg zvyr, guerr cbvag mreb avar zcu, frpbaq zvyr guerr cbvag sbhe bar zcu, gjb zvyrf, guerr cbvag gjb sbhe zcu, gjb cbvag gjb zvyrf, guerr cbvag guerr frira zcu.