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Finding the Fourth Proportional to 1,078.88, 1,618.40 and 309.38

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Solution

The fourth proportional to 1,078.88, 1,618.40 and 309.38 is: 464.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,078.88 : 1,618.40 = 309.38 : x
  2. Step 2: Convert to fraction form
    1,078.88/1,618.40 = 309.38/x
  3. Step 3: Cross multiply
    1,078.88x = 1,618.40 × 309.38
  4. Step 4: Simplify right side
    1,078.88x = 500,693.27
  5. Step 5: Solve for x
    x = 500,693.27/1,078.88
  6. Step 6: Final answer
    x = 464.09

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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.