You can find the average of 10 numbers in JavaScript using a while loop by following these steps..

• Initialize variables to keep track of the sum and count of the numbers.
• Use a while loop to repeatedly prompt the user for input until you have received 10 numbers.
• Inside the loop, add each input number to the sum and increment the count.
• After the loop, calculate the average by dividing the sum by the count.

Here's an example JavaScript code that demonstrates this:

let sum = 0;
let count = 0;

while (count < 10) {
  const input = prompt(`Enter number ${count + 1}:`);
  const number = parseFloat(input);

  if (!isNaN(number)) {
    sum += number;
    count++;
  } else {
    alert("Invalid input. Please enter a valid number.");
  }
}

if (count > 0) {
  const average = sum / count;
  alert(`The average of the 10 numbers is: ${average}`);
} else {
  alert("No valid numbers entered.");
}