Answer:
400 passengers
Step-by-step explanation:
To solve the problem, a proportion would be best!
First, let's set up the left side of the proportion. Percents, when used in parts, are always part of 100%, making 100% a whole. We'll use both 10% and 100% as our first fraction, which should look something like this:
(with <em>p </em>standing for <em>part </em>and <em>w</em> standing for the <em>whole</em>)
Next, let's set up the right side of our proportion. We'll use the 40 for our part and x for our whole since that is the number we are solving for. The proportion should now look like this:

To solve, just cross multiply and divide! Multiply 40 by 100 to give you 4,000. Next, divide 4,000 by the remaining 10 to give you a final answer of 400. If 40 passengers on the flight are in first class, then there are 400 total passengers. Hope this helps!
<span>The hour hand will go around the clock twice during a day, every 12 hours. During a single rotation, the minute hand will go around 12 times. The minute hand will pass the hour hand 11 times in the first 12 hours, and 11 times in the second 12 hours. This means that they will meet 22 times.</span>
Hi there! 5 bottles of water for $3 would make $0.60 per bottle. 0.6 * 15 = 9. That means 15 bottles of water should equal $9, but instead it is $8. Based on that, no. The costs for bottles of water is not proportional to the numbers sold. Basically, you can divide to find unit prices and multiply the number of another item to see if the numbers are proportional.