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Finding the Fourth Proportional to 400.64, 601.12 and 208.40

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Solution

The fourth proportional to 400.64, 601.12 and 208.40 is: 312.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.64 : 601.12 = 208.40 : x
  2. Step 2: Convert to fraction form
    400.64/601.12 = 208.40/x
  3. Step 3: Cross multiply
    400.64x = 601.12 × 208.40
  4. Step 4: Simplify right side
    400.64x = 125,273.41
  5. Step 5: Solve for x
    x = 125,273.41/400.64
  6. Step 6: Final answer
    x = 312.68

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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.