Question

Using the information in the passage, if you were in a room with 39 other typical adult U.S. citizens, how many of the people in the room would have prediabetes? (A) 1 (B) \(9.75\) (C) 10 (D) 60 million

Short answer

The number of people with prediabetes in the room is 10.

Step-by-step solution

Find the number of individuals

Since you are in a room with 39 other people, the total number of people in the room will be 40 people (including you). Step 2 - Calculate the proportion of people with prediabetes

Obtain the percentage of people with prediabetes

The exercise does not provide us with any information about the proportion of people with prediabetes. However, the information in the passage is necessary to answer the question. We know that \(1\) in \(4\) U.S. citizens has prediabetes, so the proportion is \(1/4\), or \(25\%\). Step 3 - Apply the proportion to the total number of people in the room

Calculate the number of people with prediabetes in the room

To find the number of people with prediabetes in the room, multiply the total number of people in the room by the proportion of people with prediabetes. So, \(40 \times (25/100) = 10\) Hence, the correct answer is (C) 10.

Key concepts

Proportion Problems

Understanding proportion problems is crucial in many real-life scenarios and standardized tests like the GED. A proportion is an equation that states two ratios are equivalent. For example, if one out of four people has prediabetes, we can write a ratio like \(1:4\) or as a fraction \(\frac{1}{4}\). When dealing with proportion problems, we often have to solve for an unknown quantity by setting up a proportion equation.

Suppose you're given the ratio of people with a certain condition in a broader population and you wish to find out how many people in a smaller group might have the condition. You'll use a proportional ratio to scale up or down to the size of the group of interest. In the GED math practice exercise, we calculated that, since 25% of the population has prediabetes, in a room with 40 people, 25% of them would also be expected to have the condition, which results in 10 individuals.

Percentage Calculations

Percentage calculations are often a part of proportion problems and are frequently tested on the GED. To convert a percentage into a decimal for calculations, you divide by 100. This step transforms a percentage, which is a proportion per hundred, into a decimal equivalent that can easily be used in mathematical operations.

In the case of our exercise: to find the number of people with prediabetes out of 40, we used the percentage 25% (which is the proportion of U.S. citizens with prediabetes). By dividing 25 by 100 to get 0.25, we then multiplied by the total number of people in the room (40) to find the number of affected individuals. Effective percentage calculations are essential for accurately solving proportion problems and are a key concept to fully grasp for success in GED math practice tests.

GED Practice Questions

GED practice questions come in various formats, including multiple choice, drag-and-drop, and fill-in-the-blank, among others. They aim to test a wide range of skills, including basic math, understanding word problems, grasping proportions, and performing percentage calculations.

In our example, the question was formulated as a word problem to be solved using proportion and percentage knowledge. Such questions help students apply mathematical concepts to practical situations. To improve at these, practice regularly, read each question carefully, and become familiar with different ways that problems may be presented. Make sure to understand the underlying concepts, as questions can often be dressed in different contexts which could be confusing if the fundamental principles are not well understood.