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Finding the Fourth Proportional to 858.50, 1,289.48 and 512.51

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Solution

The fourth proportional to 858.50, 1,289.48 and 512.51 is: 769.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.50 : 1,289.48 = 512.51 : x
  2. Step 2: Convert to fraction form
    858.50/1,289.48 = 512.51/x
  3. Step 3: Cross multiply
    858.50x = 1,289.48 × 512.51
  4. Step 4: Simplify right side
    858.50x = 660,871.39
  5. Step 5: Solve for x
    x = 660,871.39/858.50
  6. Step 6: Final answer
    x = 769.80

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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.