Node js complaining that I have not set promise

Question

I am trying to write a simple app where I ask a sequence of simple arithmetic questions and at the end tell the % correct. I started with this:

const readline = require('readline').createInterface({
  input: process.stdin,
  output: process.stdout
});

var correct = 0;
 
for (i = 0; i < 10; i++) {
  var num1 = between(0,9);
  var num2 = between(0,9);

  readline.question(num1 + " + " + num2 + " = ", answer => {
    if ((num1 + num2) == answer) {
      correct++;
    }
  });
}

console.log("percentage: " + correct/10);

function between(min, max) {  
  return Math.floor(
    Math.random() * (max - min) + min
  )
}

Then realized that I need to use Await and Promise so I switched to this:

function askQuestion(query) {
    const rl = readline.createInterface({
        input: process.stdin,
        output: process.stdout,
    });

    return new Promise(resolve => rl.question(query, ans => {
        rl.close();
        resolve(ans);
    }))
}

function between(min, max) {  
  return Math.floor(
    Math.random() * (max - min) + min
  )
}

var correct = 0;

for (i = 0; i < 10; i++) {
  var num1 = between(0,9);
  var num2 = between(0,9);

  const ans = await askQuestion(num1 + " + " + num2 + " = ");
  if (ans == (num1 + num2)) {
    correct++;
  }
}

console.log("percentage: " + (correct/10))

But I get the error

const ans = await askQuestion(num1 + " + " + num2 + " = ");
            ^^^^^

SyntaxError: await is only valid in async function

What am I doing wrong?