Click on any year from 1955 through 1995 (in the right column) and a Juke Box pops up with 20 hits of that year. (Thanks, Roger!)


Seriously! Click here. You can help a whole classful of kids.


Alan Rogowsky:This is amazing.”


Marie Coffin:Yesterday you presented ‘a little math proof’ (from your readers) of the fact that if you take a two-digit number and subtract the digits, you get a number divisible by 9. However, you’re not giving yourself enough credit. You actually proved this already in Friday‘s column. Your explanation . . . ‘Start out with 10. Subtract 1 and 0 from 10 and you get 9. From there on in, the die is cast. Because when you go up to 11, you are adding one more – but also subtracting one more. So still 9’ . . . is called ‘Proof by Induction’ – in this case, you have proved the statement not only for all two-digit numbers, but in fact for all numbers greater than or equal to 10. I think this also answers your question ‘But no women. What’s up with that?’ We were all smart enough to see that you had already provided the proof, and no further proof was needed. :)”

☞ I love it!

Tamara Hendrickson: “You note that you didn’t hear from any women. Disappointing but not surprising from my perspective. I have a Ph.D. in Bioorganic Chemistry from Caltech and I can enumerate several occasions where people of influence, including teachers, mentors, and peers, tried to hold me back with a ‘Girls can’t do math’ or ‘You will only succeed because of affirmative action’ kind of attitude. Some interferences were trivial while others were devastating. For example, when I was in 4th grade, I was in a 4th and 5th grade combination class and so I was able to do fifth grade math that year. When I got to fifth grade, my new teacher told me that she didn’t have time to teach me 6th grade math so she made me do 5th grade math again, same book and everything. Not only did I lose a year of math education but I certainly took the message home that she didn’t think I was ready for 6th grade math. I don’t know a woman scientist who doesn’t have at least one story like this. Maybe she would have taken the same attitude if I was a boy, but I can’t think of a single male scientist that I know that recalls a story of being held back or discouraged. We still live in a society where it is sometimes hard for many women to feel comfortable eagerly demonstrating math or science skills. The net effect is not only that woman are going to by shyer about writing you about things like this but also that women still seriously lag behind men in careers in math and the sciences, particularly for career paths that require graduate level education. (It is getting better every year though!) When I started my first job as a chemistry professor in 2000 I was the only female faculty member in a department of 19. It was four years before a second woman was hired. (While I am on a soapbox about women in science, I should mention that African American and Latino representation in the upper level sciences is even worse. Most chemistry departments do not have even a single faculty member of color.)

Pat F.: “If you (a) pick a number, (b) switch any number of digits and (c) subtract the larger from the smaller, the result is divisible by nine. EX: 1234 -> switch 2 and 3 to get 1324 -> 1324-1234 = 90. TA DA!! Who cares? You do. Suppose you are trying to balance your checkbook and you and the bank don’t agree. Look at the difference between you and the bank. If it is divisible by nine, you might have switched two digits in recording. I have used this and it has kept me from looking stupid in arguments with my bank.”


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