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Finding the Fourth Proportional to 509.55, 763.30 and 478.50

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Solution

The fourth proportional to 509.55, 763.30 and 478.50 is: 716.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.55 : 763.30 = 478.50 : x
  2. Step 2: Convert to fraction form
    509.55/763.30 = 478.50/x
  3. Step 3: Cross multiply
    509.55x = 763.30 × 478.50
  4. Step 4: Simplify right side
    509.55x = 365,239.05
  5. Step 5: Solve for x
    x = 365,239.05/509.55
  6. Step 6: Final answer
    x = 716.79

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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.