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Finding the Fourth Proportional to 578.40, 869.60 and 499.20

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Solution

The fourth proportional to 578.40, 869.60 and 499.20 is: 750.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    578.40 : 869.60 = 499.20 : x
  2. Step 2: Convert to fraction form
    578.40/869.60 = 499.20/x
  3. Step 3: Cross multiply
    578.40x = 869.60 × 499.20
  4. Step 4: Simplify right side
    578.40x = 434,104.32
  5. Step 5: Solve for x
    x = 434,104.32/578.40
  6. Step 6: Final answer
    x = 750.53

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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.