The L.C.M of the numbers is 420 and their GCD is 3. If one of the numbers is 60, what is the other number?

Here are the solutions to your questions:

1. The L.C.M of the numbers is 420 and their GCD is 3. If one of the numbers is 60, what is the other number?

Let the two numbers be $a$ and $b$.
Given:
LCM$(a, b) = 420$
GCD$(a, b) = 3$
One number, $a = 60$

Step 1: Use the formula: LCM$(a, b) \times$ GCD$(a, b) = a \times b$.

$$420 \times 3 = 60 \times b$$

Step 2: Simplify the equation.

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