CBSE Class 10 Maths (Standard) 2024 · Paper 30(B)/S · Question 36

Arithmetic Progressions 4 marks Medium

Hari wants to participate in a 200 m race. He can currently run that distance in 51 seconds, and with each day of practice, he hopes to take 2 seconds less than the previous day. He wants to do it in 31 seconds. Based on the above information, answer the following questions:

(i)Write the A.P. which represents the above situation.
(ii)Find the minimum number of days he needs to practice to achieve the goal. (iii)(a) Find the expression for the $n^{t h}$ term of the A.P. OR (iii)(b) If he wants to do it in 21 seconds, how many minimum days will he take?

iWrite the A.P. which represents the above situation.[1]
iiFind the minimum number of days he needs to practice to achieve the goal.[1]
iii(a)Find the expression for the $n^{t h}$ term of the A.P.[2]
iii(b)If he wants to do it in 21 seconds, how many minimum days will he take?[2]

Answer

(i) The A.P. is

51, 49, 47, 45, \dots

(times in seconds); (ii) He reaches

31

s on the 11th day, so the minimum number of days is

11

; (iii)(a)

a_{n} = 53 - 2 n

; (iii)(b)

16

days (the 16th term is

21

🔒 Step-by-step solution

From the board paper

CBSE Class 10 Maths (Standard) 2024 · Paper 30(B)/S, Question 36 — all 38 questions with answers →

CBSE Class 10 Maths (Standard) 2024 · Paper 30(B)/S · Question 36

Answer

From the board paper

More questions from Arithmetic Progressions