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Finding the Fourth Proportional to 657.70, 985.35 and 400.90

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Solution

The fourth proportional to 657.70, 985.35 and 400.90 is: 600.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.70 : 985.35 = 400.90 : x
  2. Step 2: Convert to fraction form
    657.70/985.35 = 400.90/x
  3. Step 3: Cross multiply
    657.70x = 985.35 × 400.90
  4. Step 4: Simplify right side
    657.70x = 395,026.82
  5. Step 5: Solve for x
    x = 395,026.82/657.70
  6. Step 6: Final answer
    x = 600.62

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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.