Practicing Success
Which term of the A.P : 21, 18, 15, ............. is (-81) ? |
$25^{th}$ $35^{th}$ $30^{th}$ $38^{th}$ |
$35^{th}$ |
a = 21 d = 18 - 21 = -3 . Let -81 be the nth term. Now, nth term, an= a+(n−1)d -81 = 21 + ( n -1 ) -3 n = 105/3 = 35 |