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Finding the Fourth Proportional to 1,280.00, 1,920.11 and 458.06

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Solution

The fourth proportional to 1,280.00, 1,920.11 and 458.06 is: 687.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.00 : 1,920.11 = 458.06 : x
  2. Step 2: Convert to fraction form
    1,280.00/1,920.11 = 458.06/x
  3. Step 3: Cross multiply
    1,280.00x = 1,920.11 × 458.06
  4. Step 4: Simplify right side
    1,280.00x = 879,513.70
  5. Step 5: Solve for x
    x = 879,513.70/1,280.00
  6. Step 6: Final answer
    x = 687.12

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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.