Difficulty: Medium
Average Score: 78%
Entry Exam
Ratio and proportion 0.1:10::x:400 =
Correct answer
D
Rationale
To solve this proportion, we can set it up as 0.1/10 = x/400. Cross multiply to get x = (0.1 * 400)/10 = 4. Therefore, x equals 4, making choice D the correct answer. When solving proportions, it's crucial to maintain the same relationship between the numbers on both sides of the proportion. In this case, the ratio of 0.1 to 10 should be equal to the ratio of x to 400. By cross multiplying and simplifying, we find that x is 4, confirming choice D as the correct answer.