Question

The LCM of 40, 20, 120 and 335 is:

• A. 8101
• B. 8040
• C. 8003
• D. 7991

Answer 1

Answer:

B. 8040

Let’s find the LCM of 40, 20, 120, 335.

Prime factorization

• $(40 = 2^3 \times 5)$

• $(20 = 2^2 \times 5)$

• $(120 = 2^3 \times 3 \times 5)$

• $(335 = 5 \times 67)$

  Take highest powers of each prime

• $(2^3)$

• $(3^1)$

• $(5^1)$

• $(67^1)$

  Multiply

  $\text{LCM} = 2^3 \times 3 \times 5 \times 67$
  $= 8 \times 3 \times 5 \times 67$
  $= 24 \times 5 \times 67$
  $= 120 \times 67$
  $= 8040$
  

  Final Answer: 8040