26) A

Light house 1 stays on for 3 seconds and then turns off. It stays dark for 8 seconds and then turns back on for another 3 seconds. Total time between 1st switch off and 2nd switch off = 8 + 3 = 11 seconds.

Light house 12 stays on for 2 seconds and then turns off. It stays dark for 7 seconds and then turns back on for another 2 seconds. Total time between 1st switch off and 2nd switch off = 2 + 7 = 9 seconds

To answer this question, we must list all the times when the light from lighthouses disappear:

Lighthouse 1: 3, 14, 25, 36, 47, 58, 69, 70….
Lighthouse 2: 2, 11, 20, 29, 38, 47, 56, 65…
We now know that they both turn off together after every 47 seconds. The last time they were in sync was 15 seconds off. Therefore, the next time they will be in sync would be 47-15 = 32 seconds from now.

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