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Finding the Fourth Proportional to 520.80, 780.96 and 358.56

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Solution

The fourth proportional to 520.80, 780.96 and 358.56 is: 537.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.80 : 780.96 = 358.56 : x
  2. Step 2: Convert to fraction form
    520.80/780.96 = 358.56/x
  3. Step 3: Cross multiply
    520.80x = 780.96 × 358.56
  4. Step 4: Simplify right side
    520.80x = 280,021.02
  5. Step 5: Solve for x
    x = 280,021.02/520.80
  6. Step 6: Final answer
    x = 537.67

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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.