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Finding the Fourth Proportional to 660.08, 987.70 and 400.20

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Solution

The fourth proportional to 660.08, 987.70 and 400.20 is: 598.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.08 : 987.70 = 400.20 : x
  2. Step 2: Convert to fraction form
    660.08/987.70 = 400.20/x
  3. Step 3: Cross multiply
    660.08x = 987.70 × 400.20
  4. Step 4: Simplify right side
    660.08x = 395,277.54
  5. Step 5: Solve for x
    x = 395,277.54/660.08
  6. Step 6: Final answer
    x = 598.83

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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.