CBSE Class 10 Maths (Basic) 2023 · Paper 430/C/1 · Question 37

Arithmetic Progressions 4 marks Very hard

A fashion designer is designing a fabric pattern. In each row, there are some shaded squares and unshaded triangles (see figure). Based on the pattern, answer the following questions.

Fabric pattern: in each row, shaded squares alternate with unshaded triangles (Rows 1–5 shown).

(i)Identify A.P. for the number of squares in each row.[1]
(ii)Identify A.P. for the number of triangles in each row.[1]
(iii)(a)If each shaded square is of side 2 cm, then find the shaded area when 15 rows have been designed.[2]
(iii)(b)OR Write a formula for finding total number of triangles in 'n' number of rows. Hence, find S10.[2]

Answer

(i) Squares:

1, 3, 5, 7, 9, \dots

(

a = 1

d = 2

). (ii) Triangles:

2, 6, 10, 14, 18, \dots

(

a = 2

d = 4

). (iii)(a)

S_{15} = 225

squares, shaded area

= 225 \times 4 = 900

^{2}

. (iii)(b)

S_{n} = 2 n^{2}

;

S_{10} = 200

🔒 Step-by-step solution

From the board paper

CBSE Class 10 Maths (Basic) 2023 · Paper 430/C/1, Question 37 — all 38 questions with answers →

CBSE Class 10 Maths (Basic) 2023 · Paper 430/C/1 · Question 37

Answer

From the board paper

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