# 10th CBSE math solution for exercise 5.2 part 9

This page 10th CBSE math solution for exercise 5.2 part 9 is going to provide you solution for every problems that you find in the exercise no 5.2 part 9

## 10th CBSE math solution for exercise 5.2 part 9 (19) Subba Rao started work in 1995 at an annual salary of Rs 5000 and received and increment of 200 each year. In which year did his income reach Rs.7000

Solution:

5000,5200,,...........7000

a = 5000    d = 5200 - 5000      a n = 7000

= 200

a n = a + (n - 1) d

7000 = 5000 + (n - 1) 200

7000 - 5000 = (n - 1) 200

2000 = (n - 1) 200

n - 1 = 2000/200

n - 1 = 10

n = 10 + 1

n = 11

Therefore,11th year his salary will be 7000.

(20) Ramkali saved Rs.5 in the first week of a year and then increased her weekly savings by Rs 1.75. If the nth week,her weekly savings become Rs.20.75,find n.

Solution:

a = 5  d = 1.75  an = 20.75

a n = a + (n - 1) d

20.75 = 5 + (n - 1) 1.75

20.75 - 5 = (n - 1) 1.75

15.75 = ( n - 1) 1.75

15.75/1.75 = n - 1

9 = n - 1

n - 1 = 9

n = 9 + 1

n = 10