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Finding the Fourth Proportional to 512.90, 707.79 and 280.02

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Solution

The fourth proportional to 512.90, 707.79 and 280.02 is: 386.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.90 : 707.79 = 280.02 : x
  2. Step 2: Convert to fraction form
    512.90/707.79 = 280.02/x
  3. Step 3: Cross multiply
    512.90x = 707.79 × 280.02
  4. Step 4: Simplify right side
    512.90x = 198,196.41
  5. Step 5: Solve for x
    x = 198,196.41/512.90
  6. Step 6: Final answer
    x = 386.43

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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.