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Finding the Fourth Proportional to 512.90, 707.78 and 280.04

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Solution

The fourth proportional to 512.90, 707.78 and 280.04 is: 386.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.90 : 707.78 = 280.04 : x
  2. Step 2: Convert to fraction form
    512.90/707.78 = 280.04/x
  3. Step 3: Cross multiply
    512.90x = 707.78 × 280.04
  4. Step 4: Simplify right side
    512.90x = 198,206.71
  5. Step 5: Solve for x
    x = 198,206.71/512.90
  6. Step 6: Final answer
    x = 386.44

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.