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Finding the Fourth Proportional to 688.78, 1,032.09 and 480.34

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Solution

The fourth proportional to 688.78, 1,032.09 and 480.34 is: 719.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.78 : 1,032.09 = 480.34 : x
  2. Step 2: Convert to fraction form
    688.78/1,032.09 = 480.34/x
  3. Step 3: Cross multiply
    688.78x = 1,032.09 × 480.34
  4. Step 4: Simplify right side
    688.78x = 495,754.11
  5. Step 5: Solve for x
    x = 495,754.11/688.78
  6. Step 6: Final answer
    x = 719.76

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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.