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2023 AMC 12B Question 24

AMC12 · 2023 AMC 12B

Question 24

Suppose that $a,$ $b,$ $c,$ and $d$ are positive integers satisfying all of the following relations.

$$
\begin{aligned} abcd &= 2^6\cdot 3^9\cdot 5^7\\ \operatorname{lcm}(a,b) &= 2^3\cdot 3^2\cdot 5^3\\ \operatorname{lcm}(a,c) &= 2^3\cdot 3^3\cdot 5^3\\ \operatorname{lcm}(a,d) &= 2^3\cdot 3^3\cdot 5^3\\ \operatorname{lcm}(b,c) &= 2^1\cdot 3^3\cdot 5^2\\ \operatorname{lcm}(b,d) &= 2^2\cdot 3^3\cdot 5^2\\ \operatorname{lcm}(c,d) &= 2^2\cdot 3^3\cdot 5^2 \end{aligned}
$$

What is $\gcd(a,b,c,d)?$
  1. $30$
  2. $45$
  3. $3$
  4. $15$
  5. $6$