a license plate has a three digit number parented on it. The product of the digits is 210. The sum is 18 and the numbers appear in descending order from left to right what is the license plate number?

1 answer

To find the three-digit number on the license plate that meets the given conditions, let's denote the digits as \( a \), \( b \), and \( c \) where \( a \geq b \geq c \). The conditions we need to satisfy are:

  1. \( a \cdot b \cdot c = 210 \)
  2. \( a + b + c = 18 \)

Let's start by finding the factors of 210 to identify suitable digits.

The prime factorization of 210 is: \[ 210 = 2 \times 3 \times 5 \times 7 \]

Now, we need to combine these factors into three digits (each between 0 and 9) such that their product is 210 and their sum is 18.

Let's try different combinations of digits such that their products yield 210:

  1. Looking at the individual factors: If we try \( 7 \), \( 5 \), and \( 6 \):
    • \( 7 \cdot 5 \cdot 6 = 210 \)
    • \( 7 + 5 + 6 = 18 \)

Both conditions are satisfied. Now, since the numbers must be in descending order:

Thus, the digits are \( 7, 6, 5 \), and the license plate number is 765.