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Finding the Fourth Proportional to 521.28, 780.37 and 315.23

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Solution

The fourth proportional to 521.28, 780.37 and 315.23 is: 471.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.28 : 780.37 = 315.23 : x
  2. Step 2: Convert to fraction form
    521.28/780.37 = 315.23/x
  3. Step 3: Cross multiply
    521.28x = 780.37 × 315.23
  4. Step 4: Simplify right side
    521.28x = 245,990.56
  5. Step 5: Solve for x
    x = 245,990.56/521.28
  6. Step 6: Final answer
    x = 471.90

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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.