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CBSE Sample Paper Class 10 - For 2026 Boards - If 𝑎 = 2^2 × 3^𝑥 - CBSE Class 10 Sample Paper for 2026 Boards - Maths Standard

part 2 - Question 1 - CBSE Class 10 Sample Paper for 2026 Boards - Maths Standard - Solutions of Sample Papers for Class 10 Boards - Class 10
part 3 - Question 1 - CBSE Class 10 Sample Paper for 2026 Boards - Maths Standard - Solutions of Sample Papers for Class 10 Boards - Class 10

 

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Transcript

Question 1 If 𝑎 = 22 × 3𝑥, 𝑏 = 22 × 3 × 5, 𝑐 = 22 × 3 × 7 and LCM (𝑎, 𝑏, 𝑐) = 3780, then 𝑥 is equal to (A) 1 (B) 2 (C) 3 (D) 0Given 𝑎 = 22 × 3𝑥, 𝑏 = 22 × 3 × 5, 𝑐 = 22 × 3 × 7 Finding LCM of a, b & c We take 3x since will include 3 from b and c (as long as x ≥ 1) Thus, LCM (𝑎, 𝑏, 𝑐) = 22 × 3x × 5 × 7 Also, given that LCM (𝑎, 𝑏, 𝑐) = 3780, Putting values 3780 = 22 × 3x × 5 × 7 3780 = 4 × 3x × 5 × 7 3780/(4 × 5 × 7) = 3x 3x = 𝟑𝟕𝟖𝟎/(𝟒 × 𝟓 × 𝟕) 3x = 945/(5 × 7) 3x = 189/7 3x = 27 3x = 33 Thus, x = 3 So, correct answer is (c)

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