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Finding the Fourth Proportional to 653.40, 978.90 and 550.20

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Solution

The fourth proportional to 653.40, 978.90 and 550.20 is: 824.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.40 : 978.90 = 550.20 : x
  2. Step 2: Convert to fraction form
    653.40/978.90 = 550.20/x
  3. Step 3: Cross multiply
    653.40x = 978.90 × 550.20
  4. Step 4: Simplify right side
    653.40x = 538,590.78
  5. Step 5: Solve for x
    x = 538,590.78/653.40
  6. Step 6: Final answer
    x = 824.29

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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.