1. (5 points) Using the numbers $3, 4, 7, 8,$ form two two-digit numbers (each number can only be used once, and must be used), their maximum product is $\qquad$ .
1. (5 points) Using the numbers $3, 4, 7, 8,$ form two two-digit numbers (each number can only be used once, and must be used), their maximum product is $\qquad$.

【Solution】Solution: According to the properties of multiplication and place value knowledge,
$3, 4, 7, 8$ these four numbers can form two-digit numbers,
the maximum product can be: $74 \times 83=6142$.
Therefore, the answer is: 6142.