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Finding the Fourth Proportional to 771.80, 1,156.80 and 309.35

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Solution

The fourth proportional to 771.80, 1,156.80 and 309.35 is: 463.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    771.80 : 1,156.80 = 309.35 : x
  2. Step 2: Convert to fraction form
    771.80/1,156.80 = 309.35/x
  3. Step 3: Cross multiply
    771.80x = 1,156.80 × 309.35
  4. Step 4: Simplify right side
    771.80x = 357,856.08
  5. Step 5: Solve for x
    x = 357,856.08/771.80
  6. Step 6: Final answer
    x = 463.66

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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.