Home / 1,286.27-1,929.60-420.38

Finding the Fourth Proportional to 1,286.27, 1,929.60 and 420.38

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Solution

The fourth proportional to 1,286.27, 1,929.60 and 420.38 is: 630.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.27 : 1,929.60 = 420.38 : x
  2. Step 2: Convert to fraction form
    1,286.27/1,929.60 = 420.38/x
  3. Step 3: Cross multiply
    1,286.27x = 1,929.60 × 420.38
  4. Step 4: Simplify right side
    1,286.27x = 811,165.25
  5. Step 5: Solve for x
    x = 811,165.25/1,286.27
  6. Step 6: Final answer
    x = 630.63

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.