# Video: GCSE Mathematics Foundation Tier Pack 5 • Paper 2 • Question 22

GCSE Mathematics Foundation Tier Pack 5 • Paper 2 • Question 22

03:00

### Video Transcript

Delia is making pancakes for pancake day. She buys the following ingredients: 1.5 kilograms of flour, 25 eggs, 3.6 liters of milk, 520 grams of butter. Below is a list of ingredients that Delia needs to make eight pancakes. Delia made as many pancakes as she could using the ingredients that she bought. Work out the number of pancakes Delia made.

Before we perform any calculations, it’s important that we notice that the units for flour and milk in the recipe are different to the units in the ingredients that Delia bought. We can recall that one kilogram is equal to 1000 grams. And this means we can multiply 1.5 by 1000 to work out that Delia bought 1500 grams of flour. Similarly, one liter is equal to 1000 milliliters. This means we can multiply 3.6 by 1000, and that tells us that Delia bought 3600 milliliters of milk.

We know that, to make eight pancakes, Delia needs 120 grams of flour, two eggs, 275 milliliters of milk, and 40 grams of butter. Let’s work out how many batches of eight pancakes Delia can make with 1500 grams of flour.

Since each batch requires 120 grams, we’re going to divide 1500 by 120. That’s 12 and a half batches of eight pancakes. Let’s repeat this process with the eggs. Delia bought 25 eggs, and each batch of eight pancakes requires two eggs. We can see how many batches she can make based off of her eggs by dividing 25 by two. And once again, we can see that she can make 12.5 batches of pancakes.

We do need to repeat this process for the milk and the butter just in case she hasn’t bought quite enough of these items to make 12 and a half batches. Since each batch of eight pancakes requires 275 milliliters of milk and she bought 3600 milliliters, we’re going to divide 3600 by 275. This time, that gives us 13.09 recurring, so we’re little over 13 batches of eight pancakes. Finally, she bought 520 grams of butter, and each batch requires 40. So we’re going to divide 520 by 40. That gives us 13 batches of eight pancakes.

Now in fact, she can’t quite make 13 batches of pancakes because she doesn’t have enough flour or eggs. She can make a maximum of 12.5 batches of eight pancakes. So to work out exactly how many pancakes she made, we need to multiply 12.5 by eight. 12.5 multiplied by eight is 100. So Delia made 100 pancakes.