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Finding the Fourth Proportional to 858.96, 1,288.70 and 512.68

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Solution

The fourth proportional to 858.96, 1,288.70 and 512.68 is: 769.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.96 : 1,288.70 = 512.68 : x
  2. Step 2: Convert to fraction form
    858.96/1,288.70 = 512.68/x
  3. Step 3: Cross multiply
    858.96x = 1,288.70 × 512.68
  4. Step 4: Simplify right side
    858.96x = 660,690.72
  5. Step 5: Solve for x
    x = 660,690.72/858.96
  6. Step 6: Final answer
    x = 769.18

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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.