Question

Find 100 is a term of the A.P. 25,28,31,........or not

Answer 1

$\boxed{ \huge \star \: heya \: mate \: \star} \\ \\ \color{blue} \: \: \: \: \: \: \: \underline{\bf{here \: is \: your \: answer}} \\ \\ \bf{a = 25 \: and \: d = a2 - a1 } \\ \bf{ = 28 - 25 = 3 } \\ \: \: \: \: \: \underline{\bf{ the \: formula \: is \: equal \: to - }} \\ \: \: \: \: \: \: \: \: \: \: \: \bf{a + (n - 1) \times d} \\ \\ \bf{100 = 25 + (n - 1) \times 3} \\ \bf{ 100 = 25+ 3n - 3} \\ \bf{100 = 22 + 3n} \\ \bf{78 = 3n \: or \: 3n \: = 78 } \\ \bf{ n = \frac{78}{3} = 26 } \\ \bf{so \: the \: 100 \: is \: the \: ap \: of \: 26th \: terms } \\ \\ \huge \color{green}\bf{hope \: its \: helpful}$