Sum of the sequence 9, 99, 999, 9999 up to n terms is
(10n -1) - n
9/10 (10n - 1) - n
10/9 (10n - 1) - n
None of these
The A.M between pth and qth terms of an A.P is equal to the AM between rth and sth terms of the A.P. Then p+q =
r + s
r - s/r + s
r + s/r - s
r + s + 1
The income of a person is 3,00,000 in the first year and he receives an increase of Rs. 10,000 to his income per year for the next 19 years. Then the total amount, he received in 20 years is
80,00,000
79,00,000
78,00,000
69,00,000
Which terms of the G.P 2, 2√2, 4,........ is 128?
12
13
14
15
Water flows into a tank. The volume of water in the tank at each minute form an A.P. If the initial volume was 5 litres and becomes 6 times after 6 minutes. The speed of water increase is
5 litres/min
6 litres/min
15 litres/min
2 litres/min
Given an = (n+1)2/n then a7 is
64
67
49/8
64/7
The first 3 terms of the sequence an = n+1/n+2 is
5/4, 4/3, 3/2
2/3, 3/4, 4/5
4/5, 3/4, 2/3
4, 3, 2
If G is geometric mean of numbers a and b then G =
√ab
±√ab
ab
a/b
If the sum of 3 numbers in A.P is 24 and their product is 440, then the numbers are
5, 8, 11
6, 9, 12
7, 10, 13
4, 8, 12
If the sum of n terms of an A.P is (Pn + qn2) where p and q are constants. Then the common difference is
2 + q
2q
2/q
2 - q
