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Finding the Fourth Proportional to 561.89, 842.05 and 287.40

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Solution

The fourth proportional to 561.89, 842.05 and 287.40 is: 430.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.89 : 842.05 = 287.40 : x
  2. Step 2: Convert to fraction form
    561.89/842.05 = 287.40/x
  3. Step 3: Cross multiply
    561.89x = 842.05 × 287.40
  4. Step 4: Simplify right side
    561.89x = 242,005.17
  5. Step 5: Solve for x
    x = 242,005.17/561.89
  6. Step 6: Final answer
    x = 430.70

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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.