Video Transcript
The ratio of the number of cups of diced tomatoes to the number of cups of diced cucumbers for a salad recipe is nine to seven. If a salad recipe called for three-sevenths of a cup of diced tomatoes, determine how many cups of diced cucumbers are needed.
We are told in the question that the ratio of tomatoes to cucumbers is nine to seven. We need to work out the number of cups of diced cucumbers that would be required for a recipe involving three-sevenths of a cup of diced tomatoes. There are lots of ways of approaching this problem. But remember, whatever we do to one side of the ratio we must do to the other.
Nine divided by three is equal to three. Therefore, we could work out the number of cups of diced cucumbers required for three cups of diced tomatoes by dividing seven by three. This is equal to seven-thirds. Three divided by seven is equal to three-sevenths. We could, therefore, divide seven-thirds by seven to work out the number of cups of diced cucumbers required. Seven-thirds divided by seven is equal to one-third. If a salad recipe called for three-sevenths of a cup of diced tomatoes, we would need one-third of a cup of diced cucumbers.
An alternative method which is often used in recipe problems would be to find the number of cups of cucumbers required for one cup of tomatoes first. This would work out the unit value and would allow us to scale up and down as required.
