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Finding the Fourth Proportional to 708.28, 977.43 and 397.78

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Solution

The fourth proportional to 708.28, 977.43 and 397.78 is: 548.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    708.28 : 977.43 = 397.78 : x
  2. Step 2: Convert to fraction form
    708.28/977.43 = 397.78/x
  3. Step 3: Cross multiply
    708.28x = 977.43 × 397.78
  4. Step 4: Simplify right side
    708.28x = 388,803.33
  5. Step 5: Solve for x
    x = 388,803.33/708.28
  6. Step 6: Final answer
    x = 548.94

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.