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Finding the Fourth Proportional to 561.61, 775.00 and 312.91

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Solution

The fourth proportional to 561.61, 775.00 and 312.91 is: 431.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.61 : 775.00 = 312.91 : x
  2. Step 2: Convert to fraction form
    561.61/775.00 = 312.91/x
  3. Step 3: Cross multiply
    561.61x = 775.00 × 312.91
  4. Step 4: Simplify right side
    561.61x = 242,507.97
  5. Step 5: Solve for x
    x = 242,507.97/561.61
  6. Step 6: Final answer
    x = 431.81

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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.