Question

which term of Arithmetic progression -1, 3, 7, 11 is 99

guys pls give ans only if u know,...​

Answer 1

$\huge\orange{\boxed{\bold{⋇ANSWER⋇}}}$

$a = - 1 \\ d = 7 - 3 =4 \\ tn = a + (n - 1)d \\ 99 = a + (n - 1)d \\ 99 = - 1 + (n - 1) \times 4 \\ 99 = - 1 + 4n - 4 \\ 99 = 4n - 5 \\ 4n = 99 + 5 = 104 \\ n = 104 \div 4 = 26.$

YOUR ANSWER-) 26th TERM.

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