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Finding the Fourth Proportional to 860.71, 1,288.77 and 686.56

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Solution

The fourth proportional to 860.71, 1,288.77 and 686.56 is: 1,028.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.71 : 1,288.77 = 686.56 : x
  2. Step 2: Convert to fraction form
    860.71/1,288.77 = 686.56/x
  3. Step 3: Cross multiply
    860.71x = 1,288.77 × 686.56
  4. Step 4: Simplify right side
    860.71x = 884,817.93
  5. Step 5: Solve for x
    x = 884,817.93/860.71
  6. Step 6: Final answer
    x = 1,028.01

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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.