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Finding the Fourth Proportional to 686.94, 1,028.16 and 378.06

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Solution

The fourth proportional to 686.94, 1,028.16 and 378.06 is: 565.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.94 : 1,028.16 = 378.06 : x
  2. Step 2: Convert to fraction form
    686.94/1,028.16 = 378.06/x
  3. Step 3: Cross multiply
    686.94x = 1,028.16 × 378.06
  4. Step 4: Simplify right side
    686.94x = 388,706.17
  5. Step 5: Solve for x
    x = 388,706.17/686.94
  6. Step 6: Final answer
    x = 565.85

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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.