Polish Math Exam 2026 — Task 15 | Geometric Sequence

追加: 2026-05-18

[00:00:00]Sequences are usually some of the nicer problems on the exam [music] and this year didn't disappoint.

[00:00:06]We have three terms geometric sequence so first let's calculate those terms.

[00:00:11]The first is eight, the second is 32 and the third term still have the parameter K.

[00:00:20]It's equal 3K + 5. Moving from one term to the next always means multiplying by the same number and since we [music] already know the first two terms we can calculate the related ratio is four.

[00:00:32]So now if we multiply 32 by four we get the third term 3K + 5.

[00:00:37]And from here it's just simple arithmetics and we can calculate that K is 41 and that's it. That's [music] the whole solution.