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Finding the Fourth Proportional to 420.71, 631.06 and 228.47

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Solution

The fourth proportional to 420.71, 631.06 and 228.47 is: 342.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.71 : 631.06 = 228.47 : x
  2. Step 2: Convert to fraction form
    420.71/631.06 = 228.47/x
  3. Step 3: Cross multiply
    420.71x = 631.06 × 228.47
  4. Step 4: Simplify right side
    420.71x = 144,174.55
  5. Step 5: Solve for x
    x = 144,174.55/420.71
  6. Step 6: Final answer
    x = 342.70

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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.