NCERT Arithmetic Progressions Word Problems MCQs – Real-Life Applications
NCERT Arithmetic Progressions Word Problems MCQs – Real-Life Applications
Class: 10
Subject: Mathematics
Chapter 5: Arithmetic Progressions
Based on: Latest CBSE Board Examination Pattern
Q1. A worker’s daily wage increases by ₹20 every day. If his wage on first day is ₹300, what will be his wage on 10th day?
Correct Answer: B. ₹480
Here, a = 300, d = 20, n = 10.
a₁₀ = a + (n−1)d = 300 + 9×20 = 300 + 180 = ₹480.
a₁₀ = a + (n−1)d = 300 + 9×20 = 300 + 180 = ₹480.
Q2. The number of trees planted in rows increases by 5 each row. If first row has 15 trees, how many trees are in 8th row?
Correct Answer: B. 50
a=15, d=5, n=8.
a₈ = 15 + 7×5 = 15 + 35 = 50.
a₈ = 15 + 7×5 = 15 + 35 = 50.
Q3. A theatre has 20 seats in first row and each successive row has 3 more seats. How many seats are in 15th row?
Correct Answer: C. 62
a=20, d=3, n=15.
a₁₅ = 20 + 14×3 = 20 + 42 = 62.
a₁₅ = 20 + 14×3 = 20 + 42 = 62.
Q4. How many terms of AP: 7, 10, 13,... are required to get sum 406?
Correct Answer: C. 16
a=7, d=3.
Sₙ = n/2[2a+(n−1)d]=406.
n/2[14+3(n−1)]=406 → solving gives n=16.
Sₙ = n/2[2a+(n−1)d]=406.
n/2[14+3(n−1)]=406 → solving gives n=16.
Q5. If the sum of first n natural numbers is 210, find n.
Correct Answer: B. 20
Sₙ = n(n+1)/2 = 210.
n(n+1)=420 → n=20.
n(n+1)=420 → n=20.
Q6. A man saves ₹100 in first month and increases saving by ₹50 each month. How much does he save in 12th month?
Correct Answer: C. ₹750
a=100, d=50, n=12.
a₁₂=100+11×50=750.
a₁₂=100+11×50=750.
Q7. Find the 25th term of AP: 3, 7, 11,...
Correct Answer: C. 99
a=3,d=4,n=25.
a₂₅=3+24×4=99.
a₂₅=3+24×4=99.
Q8. How many multiples of 4 lie between 10 and 250?
Correct Answer: B. 60
Multiples: 12 to 248.
a=12,d=4,l=248.
n=60.
a=12,d=4,l=248.
n=60.
Q9. Find sum of first 30 even numbers.
Correct Answer: B. 930
Sum of first n even numbers = n(n+1).
30×31=930.
30×31=930.
Q10. A car travels 20 km first hour and increases by 5 km each hour. Distance in 6th hour?
Correct Answer: B. 45
a=20,d=5,n=6.
a₆=20+5×5=45.
a₆=20+5×5=45.
Q11. Find 18th term of AP: 5,9,13...
Correct Answer: A. 73
5+17×4=73.
Q12. How many terms in AP: 2,5,8... are needed to get 406?
Correct Answer: C. 28
aₙ=2+(n−1)3=83 gives n=28.
Q13. Sum of first 15 terms of AP: 4,9,14...
Correct Answer: C. 615
Use Sₙ formula.
Q14. Find 40th term of AP: 1,4,7...
Correct Answer: B. 118
1+39×3=118.
Q15. If a=6,d=2 find a₂₀.
Correct Answer: B. 44
6+19×2=44.
Q16. Sum of first 25 odd numbers?
Correct Answer: A. 625
n²=25²=625.
Q17. Find n if nth term of AP 3,7,11 is 99.
Correct Answer: C. 25
3+(n−1)4=99 → n=25.
Q18. A ladder increases height by 2 cm per step. First step 10 cm. Height at 15th step?
Correct Answer: B. 38
10+14×2=38.
Q19. Find sum of first 20 terms of AP: 3,6,9...
Correct Answer: B. 630
Sₙ=n/2[2a+(n−1)d]=630.
Q20. How many two-digit numbers are divisible by 3?
Correct Answer: B. 30
From 12 to 99, AP count=30.
