You are here
Question 4 - End-of-Chapter Exercises - Chapter 8 - Predicting What Comes Next: Exploring Sequences & Progress
Last updated at June 9, 2026 by Teachoo
End-of-Chapter Exercises
Class 9
Chapter 8 - Predicting What Comes Next: Exploring Sequences & Progress
- Definition
- Explicit Rule for a Sequence
- Recursive Rule for a Sequence
- Virahānka–Fibonacci sequence
- Exercise Set 8.1
- Arithmetic Progressions
- Visualising an AP
- Sum of the First n Natural Numbers
- Exercise Set 8.2
- Geometric Progressions
- Fractals as a GP Sequence
- Visualising a GP
- Exercise Set 8.3
-
End-of-Chapter Exercises
Transcript
Question 4 How many multiples of 4 lie between 10 and 250 ? (Hint: All multiples of 4 form an AP. Find the smallest and largest multiples of 4 between 10 and 250.) Multiple of 4 are 4, 8, 12, 16, …. Let’s find the smallest and largest multiples of 4 between 10 & 250 Smallest multiple 10/4 = 22/4 11/4 = 23/4 𝟏𝟐/𝟒 = 3 ∴ Smallest multiple = 12 Largest multiple 250/4 = 622/4 249/4 = 621/4 𝟐𝟒𝟖/𝟒 = 62 ∴ Largest multiple = 248 Now, our multiples 7 form an AP The AP is 12, 16, 20, … 248 Where First term = a = 12 Common difference = d = 4 Last term = an = 248 We need to find number of terms, i.e., n Putting values in formula an = a + (n – 1) d 248 = 12 + (n – 1) 4 248 = 12 + 4n – 4 248 = 8 + 4n 248 – 8 = 4n 240 = 4n n = 240/4 n = 60 So, 60 multiples of 4 lie between 10 and 250
