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Finding the Fourth Proportional to 686.88, 1,028.88 and 302.40

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Solution

The fourth proportional to 686.88, 1,028.88 and 302.40 is: 452.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.88 : 1,028.88 = 302.40 : x
  2. Step 2: Convert to fraction form
    686.88/1,028.88 = 302.40/x
  3. Step 3: Cross multiply
    686.88x = 1,028.88 × 302.40
  4. Step 4: Simplify right side
    686.88x = 311,133.31
  5. Step 5: Solve for x
    x = 311,133.31/686.88
  6. Step 6: Final answer
    x = 452.97

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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.