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Finding the Fourth Proportional to 653.85, 978.98 and 509.85

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Solution

The fourth proportional to 653.85, 978.98 and 509.85 is: 763.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.85 : 978.98 = 509.85 : x
  2. Step 2: Convert to fraction form
    653.85/978.98 = 509.85/x
  3. Step 3: Cross multiply
    653.85x = 978.98 × 509.85
  4. Step 4: Simplify right side
    653.85x = 499,130.40
  5. Step 5: Solve for x
    x = 499,130.40/653.85
  6. Step 6: Final answer
    x = 763.37

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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.