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Finding the Fourth Proportional to 561.78, 775.28 and 313.18

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Solution

The fourth proportional to 561.78, 775.28 and 313.18 is: 432.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.78 : 775.28 = 313.18 : x
  2. Step 2: Convert to fraction form
    561.78/775.28 = 313.18/x
  3. Step 3: Cross multiply
    561.78x = 775.28 × 313.18
  4. Step 4: Simplify right side
    561.78x = 242,801.04
  5. Step 5: Solve for x
    x = 242,801.04/561.78
  6. Step 6: Final answer
    x = 432.20

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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.