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Finding the Fourth Proportional to 251.78, 347.02 and 210.20

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Solution

The fourth proportional to 251.78, 347.02 and 210.20 is: 289.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    251.78 : 347.02 = 210.20 : x
  2. Step 2: Convert to fraction form
    251.78/347.02 = 210.20/x
  3. Step 3: Cross multiply
    251.78x = 347.02 × 210.20
  4. Step 4: Simplify right side
    251.78x = 72,941.34
  5. Step 5: Solve for x
    x = 72,941.34/251.78
  6. Step 6: Final answer
    x = 289.71

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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.