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Finding the Fourth Proportional to 421.61, 632.39 and 147.71

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Solution

The fourth proportional to 421.61, 632.39 and 147.71 is: 221.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.61 : 632.39 = 147.71 : x
  2. Step 2: Convert to fraction form
    421.61/632.39 = 147.71/x
  3. Step 3: Cross multiply
    421.61x = 632.39 × 147.71
  4. Step 4: Simplify right side
    421.61x = 93,411.17
  5. Step 5: Solve for x
    x = 93,411.17/421.61
  6. Step 6: Final answer
    x = 221.56

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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.