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Finding the Fourth Proportional to 423.02, 634.80 and 407.90

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Solution

The fourth proportional to 423.02, 634.80 and 407.90 is: 612.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    423.02 : 634.80 = 407.90 : x
  2. Step 2: Convert to fraction form
    423.02/634.80 = 407.90/x
  3. Step 3: Cross multiply
    423.02x = 634.80 × 407.90
  4. Step 4: Simplify right side
    423.02x = 258,934.92
  5. Step 5: Solve for x
    x = 258,934.92/423.02
  6. Step 6: Final answer
    x = 612.11

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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.