Class X Worksheet 1 Arithmetic Progressions Important Question For Board Exams : Unsolved

 Arithmetic progressions: Unsolved Worksheet 1

1. Find the common difference of given AP: 1/a, 3-a/3a, 3-2a/3a,....... (a≠0).

2. How many two digits numbers are divisible by 3?

3. In an AP, if the common difference (d) = -4 and the seventh term (a7) is 4, then find the first term.

4. What is the common difference of an AP in which a21-a7=84?

5. For what value of k will k+9, 2k-1 and 2k+7 are the consecutive terms of an AP?

6. Find the 9th term from the end(towards the first term) of the AP 5, 9, 13,......, 185.

7. Find the sum of first 20 terms of the following AP 1, 4, 7, 10,............

8. The sum of the first 7 terms of an AP is 63 and that of its next 7 terms of an AP is 63 and that of its next 7 terms is 161. Find the AP.

9. Which term of the AP 3, 15, 27, 39, ..... will be 120 more than its 21st term?

10. Find, how many two digit natural numbers are divisible by 7?