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Finding the Fourth Proportional to 886.78, 1,330.20 and 309.70

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Solution

The fourth proportional to 886.78, 1,330.20 and 309.70 is: 464.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    886.78 : 1,330.20 = 309.70 : x
  2. Step 2: Convert to fraction form
    886.78/1,330.20 = 309.70/x
  3. Step 3: Cross multiply
    886.78x = 1,330.20 × 309.70
  4. Step 4: Simplify right side
    886.78x = 411,962.94
  5. Step 5: Solve for x
    x = 411,962.94/886.78
  6. Step 6: Final answer
    x = 464.56

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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.