### Video Transcript

A leak in a shower head wastes 23 liters of water every week. How many milliliters is wasted?

You’ve ever wondered how much water a dripping tap wastes, just look at how much water a leak in a shower head wastes. We’re told that 23 liters of water are wasted every week. The question asks us, how many milliliters is wasted? Look at how the fact we’re given and then the question both use different units of measurement. We’re given a piece of information in liters, but the question asks us for our answer in milliliters. So, to answer correctly, we need to be able to convert from liters into milliliters.

And to be able to do this, we need to understand how many milliliters there are in a liter. Let’s remind ourselves. One liter is the same as 1000 milliliters. And we can use this fact to help us solve the problem. Because there are 1000 milliliters in a liter, to convert liters into milliliters, we need to multiply by 1000. So, in this particular problem, we need to multiply 23 by 1000. You probably know what the answer is going to be already, but let’s show how it works using a place value grid.

Now, if we were to write the number 23, we’d write the digit two in the tens place and three in the ones place. But if we’re multiplying by 1000, each of these digits becomes worth 1000 times as big. When we move a digit one place to the left, it becomes 10 times as large. This means that two places to the left makes it 100 times as large. And three jumps to the left makes it 1000 times as large, which is what we want.

So, let’s shift our two digits three places to the left. One, we need to put a zero in as a placeholder to show that we’ve got this empty ones place, two, three. 23 multiplied by 1000 equals 23000. If a leak in a showerhead wastes 23 liters of water every week, the number of milliliters that is wasted is 23000 milliliters.