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Finding the Fourth Proportional to 847.60, 1,271.40 and 539.80

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Solution

The fourth proportional to 847.60, 1,271.40 and 539.80 is: 809.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    847.60 : 1,271.40 = 539.80 : x
  2. Step 2: Convert to fraction form
    847.60/1,271.40 = 539.80/x
  3. Step 3: Cross multiply
    847.60x = 1,271.40 × 539.80
  4. Step 4: Simplify right side
    847.60x = 686,301.72
  5. Step 5: Solve for x
    x = 686,301.72/847.60
  6. Step 6: Final answer
    x = 809.70

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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.