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Finding the Fourth Proportional to 660.47, 990.56 and 430.97

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Solution

The fourth proportional to 660.47, 990.56 and 430.97 is: 646.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.47 : 990.56 = 430.97 : x
  2. Step 2: Convert to fraction form
    660.47/990.56 = 430.97/x
  3. Step 3: Cross multiply
    660.47x = 990.56 × 430.97
  4. Step 4: Simplify right side
    660.47x = 426,894.54
  5. Step 5: Solve for x
    x = 426,894.54/660.47
  6. Step 6: Final answer
    x = 646.35

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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.