Hidden AP Term Challenge

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Question

In an AP, a3=7a_3=7 and a7=19.a_7=19. Find a15.a_{15}.
a₃ = 7a₇ = 19a₁₅ = ?Count the jumps from term 1 to term 3

Starting at the first term, how many equal jumps are needed to reach the third term?

What you will learn

Turn known AP terms into equations, find the first term and common difference, and calculate a later term.

Common mistake to avoid

The term number is not the number of jumps; the number of jumps is one less.

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