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Arithematic Progressions

Two APs have the same common difference. The first term of one AP is 2 and that of the other is 7. The difference between their 10th terms is the same as the difference between their 21st terms, which is the same as the difference between any two corresponding terms. Why?

Arithematic Progressions

For the AP: –3, –7, –11, …, can we find directly a₃₀ – a₂₀  without actually finding a₃₀ and a₂₀? Give reasons for your answer.

Arithematic Progressions

Which of the following form an AP? Justify your answer.

(i) –1, –1, –1, –1, …

(ii) 0, 2, 0, 2, …

(iii) 1, 1, 2, 2, 3, 3,…

(iv) 11, 22, 33,…

(v) 1/2, 1/3, 1/4…..

(vi)  2, 2², 2³, 2⁴, …

Arithematic Progressions

The n^th term of an AP cannot be n² + 1. Justify your answer.

Arithematic Progressions

Divya deposited Rs 1000 at compound interest at the rate of 10% per annum. The amounts at the end of first year, second year, third year, …, form

Arithematic Progressions

 In the AP: 10, 5, 0, –5, … the common difference d is equal to 5. Justify whether the above statement is true or false.

Arithematic Progressions

The sum of first five multiples of 3 is

(A)  45 (B)  55 (C)  65 (D)  75

Arithematic Progressions

In an AP if a = 1, a_n = 20 and S_n = 399, then n is

(A) 19 (B)  21 (C)  38 (D)  42

Arithematic Progressions

The sum of first 16 terms of the AP: 10, 6, 2,… is

(A) –320 (B) 320 (C) –352 (D) –400

Arithematic Progressions

If the first term of an AP is –5 and the common difference is 2, then the sum of the first 6 terms is

(A)  0 (B)  5 (C)  6 (D)  15