Maths, clearly

# Errata: The Maths Behind

p11: The figure for flying in the green circle should be 1000 miles. (12,000 miles refers to the risk specifically from terrorism.)

p19: 50 names, rather than 40, would have died out.

p26: Israel’s nuclear arsenal is believed to be around 80, rather than 80-20.

p29: where I have “(but not the obligation) to buy”, I should have “… to sell”. Further, in both inequalities, x should be P.

p30: The first = in the Black-Scholes equation should be a +.

p43: hexagons in fact have the smallest perimeter-to-area ratio.

p55: I have “ten-thousandth of a newton”; it should be “hundred-thousandth”.

p68: 65 is in fact, 1 000 001 in binary, and 101 is 1 100 101.

p71: There is an error in the formula. It should read “Total people up to level $n$: $\frac{6\left(6^n – 5\right)}{5}$. Similarly, the last formula should read $k^n -1$ rather than $k^{n-1}$. The blue circle should say “13” rather than 12.

p74: I have miscounted and miscalculated here. I think a G has disappeared from the analysis and several knock-on errors have occurred. Gracias to my Spanish translator for spotting this!

p83: Start and End should be switched.

p97: “better” should not be in the green circle.

p115: you can’t solve (6/7)^N. You can solve $\left(\frac{6}{7}\right)^N = 0.5$, which is what I meant.

p117: Typo – for Bond Sreet, read Bond Street.

p129: Typo – “if Mother” should have a capital I.

p133: The graphs here are a mess, and I’m not sure what I was trying to get across with them.

p150: The bottom line of the figure should read “Accelerates to 3”

p151: The 45-minute roads are A to Y and B to X.

p158: The wing pictured is not practical for flying. The underside should be less curved than the top.

p166: We’ve typeset $\sqrt{\frac{n}{2}}$ rather than $\frac{\sqrt{n}}{2}$.

p169: The picture does not match the description. Hopefully you can mentally rename the shapes as appropriate.

p170: 3 in 56 is about 1 in 19, not 1 in 17. I am not certain why the graph shows statistics for a 45-ball lottery, something the UK has never had.

p177: There is a 99.7% chance of a mismatch, not of a match; the labels in the figure are reversed.

p181: A ‘ln’ has gone missing; it would in fact score $\ln\left(\frac{0.8}{0.2}\right)$.

p184: Embarrassingly, I referred to the winter solstice as an equinox. Good grief.

p185: There is an error in the diagram; the lower arrow does not belong and the caption should read “extra evening daylight”.