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Finding the Fourth Proportional to 520.50, 780.18 and 459.78

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Solution

The fourth proportional to 520.50, 780.18 and 459.78 is: 689.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.50 : 780.18 = 459.78 : x
  2. Step 2: Convert to fraction form
    520.50/780.18 = 459.78/x
  3. Step 3: Cross multiply
    520.50x = 780.18 × 459.78
  4. Step 4: Simplify right side
    520.50x = 358,711.16
  5. Step 5: Solve for x
    x = 358,711.16/520.50
  6. Step 6: Final answer
    x = 689.17

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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.