The 18th Term Mystery

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Arithmetic ProgressionsVideo challenge · SAV50

The 18th Term Mystery

CBSE Class 10 · Solve it one decision at a time. A wrong pick earns a nudge, never the answer.

Step 1 of 6

The problem

If 77 times the 7th7^{\text{th}} term of an Arithmetic Progression is equal to 1111 times its 11th11^{\text{th}} term, find its 18th18^{\text{th}} term.

Step 1 · Your move

Before the guided steps, what value did you get for the 18th18^{\text{th}} term?

7⋅a7=11⋅a117 \cdot a_7 = 11 \cdot a_{11}
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