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Finding the Fourth Proportional to 656.31, 905.70 and 407.61

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Solution

The fourth proportional to 656.31, 905.70 and 407.61 is: 562.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.31 : 905.70 = 407.61 : x
  2. Step 2: Convert to fraction form
    656.31/905.70 = 407.61/x
  3. Step 3: Cross multiply
    656.31x = 905.70 × 407.61
  4. Step 4: Simplify right side
    656.31x = 369,172.38
  5. Step 5: Solve for x
    x = 369,172.38/656.31
  6. Step 6: Final answer
    x = 562.50

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.