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Finding the Fourth Proportional to 520.45, 780.78 and 155.23

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Solution

The fourth proportional to 520.45, 780.78 and 155.23 is: 232.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.45 : 780.78 = 155.23 : x
  2. Step 2: Convert to fraction form
    520.45/780.78 = 155.23/x
  3. Step 3: Cross multiply
    520.45x = 780.78 × 155.23
  4. Step 4: Simplify right side
    520.45x = 121,200.09
  5. Step 5: Solve for x
    x = 121,200.09/520.45
  6. Step 6: Final answer
    x = 232.88

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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.