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Finding the Fourth Proportional to 858.12, 1,288.80 and 512.52

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Solution

The fourth proportional to 858.12, 1,288.80 and 512.52 is: 769.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.12 : 1,288.80 = 512.52 : x
  2. Step 2: Convert to fraction form
    858.12/1,288.80 = 512.52/x
  3. Step 3: Cross multiply
    858.12x = 1,288.80 × 512.52
  4. Step 4: Simplify right side
    858.12x = 660,535.78
  5. Step 5: Solve for x
    x = 660,535.78/858.12
  6. Step 6: Final answer
    x = 769.75

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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.