Find the smallest 4 digit number which is divisible by 18, 24, 32?
2024
Find the smallest 4 digit number which is divisible by 18, 24, 32?
- A.
1152
- B.
1512
- C.
1216
- D.
1680
Attempted by 66 students.
Show answer & explanation
Correct answer: A
Key idea: find the least common multiple (LCM) of the three numbers, then find the smallest 4-digit multiple of that LCM.
Prime factorization: 18 = 2 × 3², 24 = 2³ × 3, 32 = 2⁵.
LCM = 2⁵ × 3² = 32 × 9 = 288.
Smallest 4-digit multiple: compute ceil(1000 ÷ 288) = 4, so 288 × 4 = 1152.
1152 ÷ 18 = 64
1152 ÷ 24 = 48
1152 ÷ 32 = 36
Answer: 1152