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Finding the Fourth Proportional to 771.40, 1,155.02 and 539.80

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Solution

The fourth proportional to 771.40, 1,155.02 and 539.80 is: 808.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    771.40 : 1,155.02 = 539.80 : x
  2. Step 2: Convert to fraction form
    771.40/1,155.02 = 539.80/x
  3. Step 3: Cross multiply
    771.40x = 1,155.02 × 539.80
  4. Step 4: Simplify right side
    771.40x = 623,479.80
  5. Step 5: Solve for x
    x = 623,479.80/771.40
  6. Step 6: Final answer
    x = 808.24

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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.