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Finding the Fourth Proportional to 912.52, 1,368.85 and 287.90

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Solution

The fourth proportional to 912.52, 1,368.85 and 287.90 is: 431.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    912.52 : 1,368.85 = 287.90 : x
  2. Step 2: Convert to fraction form
    912.52/1,368.85 = 287.90/x
  3. Step 3: Cross multiply
    912.52x = 1,368.85 × 287.90
  4. Step 4: Simplify right side
    912.52x = 394,089.06
  5. Step 5: Solve for x
    x = 394,089.06/912.52
  6. Step 6: Final answer
    x = 431.87

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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.