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Finding the Fourth Proportional to 770.38, 1,155.67 and 308.21

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Solution

The fourth proportional to 770.38, 1,155.67 and 308.21 is: 462.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.38 : 1,155.67 = 308.21 : x
  2. Step 2: Convert to fraction form
    770.38/1,155.67 = 308.21/x
  3. Step 3: Cross multiply
    770.38x = 1,155.67 × 308.21
  4. Step 4: Simplify right side
    770.38x = 356,182.50
  5. Step 5: Solve for x
    x = 356,182.50/770.38
  6. Step 6: Final answer
    x = 462.35

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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.