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Finding the Fourth Proportional to 509.55, 703.02 and 312.90

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Solution

The fourth proportional to 509.55, 703.02 and 312.90 is: 431.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.55 : 703.02 = 312.90 : x
  2. Step 2: Convert to fraction form
    509.55/703.02 = 312.90/x
  3. Step 3: Cross multiply
    509.55x = 703.02 × 312.90
  4. Step 4: Simplify right side
    509.55x = 219,974.96
  5. Step 5: Solve for x
    x = 219,974.96/509.55
  6. Step 6: Final answer
    x = 431.70

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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.