*Spoilers for last week’s fivethirtyeight.com Riddler Express and Classic:*

# Express

From Charlie Drinnan, find the letters’ numbers:

If A, B, C, D and E are all unique digits, what values would work with the following equation?

ABC,CDE × 4 = EDC,CBA

No problem. must be even, and , so . Then so , and so and , or and . But so .

Now so . so .

Finally or , so .

.

# Classic

This is fairly mechanical although I tripped up several times on the way.

Let be the number of coconuts found by the th pirate, and be the number of coconuts found in the morning. is divisible by 7 so write .

But is what was left when the seventh pirate discarded one coconut out of and hid one seventh of the rest, so . For that to be an integer must be a multiple of 6, so write . Then .

Now . For integer value, , so write . Then .

You see how this goes.

. For integer value, , so write . Then .

. For integer value, , so write . Then .

. For integer value, , so write . Then .

. For integer value, , so write . Then .

. For integer value, , so write . Then . The smallest value corresponds to so .

These pirates were either very sleepy, or incredibly quick at counting coconuts.