A person is to count 4500 currency notes. Let `a_n` denote the number of notes he counts is the `n^(th)` minute .If `a_1=a_2` =…… `=a_10`= 150 and `a_10,a_11..,` are in A.P with common difference -2, then the time to count all notes

A person is to count 4500 currency notes. Let a_n , denote the number of notes he counts in the nth minute if a_1=a_2=a_3=..........=a_10=150 and a_10,a_11,......... are in an AP with common difference -2 , then the time taken by him to count all notes is :- (1) 24 minutes 10 11 (2) 34 minutes (3) 125 minutes (4) 135 minutes

A person is to count 4500 currency notes. Let an denote the number of notes he counts in the nth minute. If a_1=""a_2="". . . . . .""=""a_(10)=""150 and a_(10),""a_(11),"". . . . . . are in A.P. with common difference -2, then the time taken by him to count all notes is (1) 34 minutes (2) 125 minutes (3) 135 minutes (4) 24 minutes

A cricketer has to score 4500 runs. Let a _(n) denotes the number of runs he scores in the n ^(th) match. If a _(1)=a_(2)= …. a _(10) =150 and a _(10) , a _(11), a_(12)…. are in A.P. with common difference (-2) . If N be the total number of matches played by him to scoere 4500 runs. Find the sum of the digits of N.

A sequence a_n , n in N be an A.P. such that a_7 = 9 and a_1 a_2 a_7 is least, then the common difference is:

Let A_1 , A_2 …..,A_3 be n arithmetic means between a and b. Then the common difference of the AP is

Find the number of all three elements subsets of the set {a_1, a_2, a_3, a_n} which contain a_3dot

A cashier has to count a bundle of Rs. 12,000 one rupee notes. He counts at the rate of Rs. 150 per minute for an hour, at the end of which he begins to count at the rate of Rs. 2 less every minute then he did the previous minute. Find how long he will take to finish his task and explain the double answer.

Let a_n be the nth therm of a G.P of positive numbers .Let Sigma_(n=1)^(100) a_(2n)=alpha and Sigma_(n=1)^(100)a_(an-1)=beta then the common ratio is

Let a_1,a_2 ,…. , a_10 be in A.P. and h_1,h_2 …. h_10 be in H.P. If a_1=h_1=2 and a_10 = h_10 =3 , then a_4 h_7 is :

If a_1,a_2,a_3,…………..a_n are in A.P. whose common difference is d, show tht sum_2^ntan^-1 d/(1+a_(n-1)a_n)= tan^-1 ((a_n-a_1)/(1+a_na_1))