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Finding the Fourth Proportional to 661.90, 992.85 and 455.85

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Solution

The fourth proportional to 661.90, 992.85 and 455.85 is: 683.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.90 : 992.85 = 455.85 : x
  2. Step 2: Convert to fraction form
    661.90/992.85 = 455.85/x
  3. Step 3: Cross multiply
    661.90x = 992.85 × 455.85
  4. Step 4: Simplify right side
    661.90x = 452,590.67
  5. Step 5: Solve for x
    x = 452,590.67/661.90
  6. Step 6: Final answer
    x = 683.78

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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.