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Finding the Fourth Proportional to 505.20, 708.90 and 505.20

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Solution

The fourth proportional to 505.20, 708.90 and 505.20 is: 708.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.20 : 708.90 = 505.20 : x
  2. Step 2: Convert to fraction form
    505.20/708.90 = 505.20/x
  3. Step 3: Cross multiply
    505.20x = 708.90 × 505.20
  4. Step 4: Simplify right side
    505.20x = 358,136.28
  5. Step 5: Solve for x
    x = 358,136.28/505.20
  6. Step 6: Final answer
    x = 708.90

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.