Arithmetic Progressions — Question Ex 5.1 Q1
Back to all questionsIn which of the following situations, does the list of numbers involved make an arithmetic progression and why?
(i) The taxi fare after each km when the fare is ₹ 15 for the first km and ₹ 8 for each additional km.
(ii) The amount of air present in a cylinder when a vacuum pump removes \(\frac { 1 }{ 4 }\) of the air remaining in the cylinder at a time.
(iii) The cost of digging a well after every meter of digging, when it costs ₹ 150 for the first meter and rises by ₹ 50 for each subsequent meter.
(iv) The amount of money in the account every year, when ₹ 10000 is deposited at compound interest at 8% per annum.
CBSE Class 10 Arithmetic Progressions — Complete Guide
AP is a high-scoring chapter carrying 5-6 marks. The nth term and sum formulae appear in every board exam.
Quick Revision: Key Concepts
- AP: a, a+d, a+2d, ... (constant common difference)
- nth term: an = a + (n−1)d
- Sum: Sn = n/2[2a + (n−1)d] = n/2(a + l)
- Key relation: an = Sn − Sn−1
Most Important Questions
- Find specific terms (nth term, last term)
- Find sum of first n terms
- Find number of terms when sum is given
- Application problems (salary, savings, stacking)
About Bright Tutorials
Bright Tutorials, Hariom Nagar, Nashik Road, provides expert coaching for CBSE and ICSE students. Our experienced faculty ensures comprehensive preparation for board exams with personalised attention and 3-tier differentiation for students of all levels. Contact us at 9403781999 or visit brighttutorials.in.