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Finding the Fourth Proportional to 838.70, 1,256.55 and 404.90

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Solution

The fourth proportional to 838.70, 1,256.55 and 404.90 is: 606.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    838.70 : 1,256.55 = 404.90 : x
  2. Step 2: Convert to fraction form
    838.70/1,256.55 = 404.90/x
  3. Step 3: Cross multiply
    838.70x = 1,256.55 × 404.90
  4. Step 4: Simplify right side
    838.70x = 508,777.10
  5. Step 5: Solve for x
    x = 508,777.10/838.70
  6. Step 6: Final answer
    x = 606.63

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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.