## '

### Arithmetic Progression

Arithmetic Progression
One Hour Test
1. How many two-digit numbers are divisible by 3?
2. Find the 11th term from the last term  of the AP : 10, 7, 4, . . ., – 62.
3. A sum of Rs 1000 is invested at 8% simple interest per year. Calculate the interest at the end of each year. Do these interests form an AP? If so, find the interest at the end of 30 years
4. In a flower bed, there are 23 rose plants in the first row, 21 in the second, 19 in the third, and so on.There are 5 rose plants in the last row. How many rows are there in the flower bed?
5. If the sum of the first 14 terms of an AP is 1050 and its first term is 10, find the 20th term.
6. A manufacturer of TV sets produced 600 sets in the third year and 700 sets in the seventh year Assuming that the production increases uniformly by a fixed number every year, find : the production in the 1st year (ii) the production in the 10th year (iii) the total production in first 7 years
7. 200 logs are stacked in the following manner: 20 logs in the bottom row, 19 in the next row, 18 in the row next to it and so on  In how may rows are the 200 logs placed and how many logs are in the top row?
8. A spiral is made up of successive semicircles, with centres alternately at A and B, starting with centre at A, of radii 0.5 cm, 1.0 cm, 1.5 cm, 2.0 cm, . . .  What is the total length of such a spiral made up of thirteen  consecutive  semicircles?
9. If the 3rd and the 9th terms of an AP are 4 and – 8 respectively, which term of this AP is zero?
10. For what value of n, are the nth terms of two APs: 63, 65, 67, . . . and 3, 10, 17, . . . equal?