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Finding the Fourth Proportional to 497.30, 686.50 and 300.78

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Solution

The fourth proportional to 497.30, 686.50 and 300.78 is: 415.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    497.30 : 686.50 = 300.78 : x
  2. Step 2: Convert to fraction form
    497.30/686.50 = 300.78/x
  3. Step 3: Cross multiply
    497.30x = 686.50 × 300.78
  4. Step 4: Simplify right side
    497.30x = 206,485.47
  5. Step 5: Solve for x
    x = 206,485.47/497.30
  6. Step 6: Final answer
    x = 415.21

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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.