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Finding the Fourth Proportional to 852.90, 1,280.10 and 505.80

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Solution

The fourth proportional to 852.90, 1,280.10 and 505.80 is: 759.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    852.90 : 1,280.10 = 505.80 : x
  2. Step 2: Convert to fraction form
    852.90/1,280.10 = 505.80/x
  3. Step 3: Cross multiply
    852.90x = 1,280.10 × 505.80
  4. Step 4: Simplify right side
    852.90x = 647,474.58
  5. Step 5: Solve for x
    x = 647,474.58/852.90
  6. Step 6: Final answer
    x = 759.14

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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.