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Finding the Fourth Proportional to 686.79, 1,030.20 and 275.82

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Solution

The fourth proportional to 686.79, 1,030.20 and 275.82 is: 413.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.79 : 1,030.20 = 275.82 : x
  2. Step 2: Convert to fraction form
    686.79/1,030.20 = 275.82/x
  3. Step 3: Cross multiply
    686.79x = 1,030.20 × 275.82
  4. Step 4: Simplify right side
    686.79x = 284,149.76
  5. Step 5: Solve for x
    x = 284,149.76/686.79
  6. Step 6: Final answer
    x = 413.74

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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.