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Finding the Fourth Proportional to 640.31, 960.24 and 315.90

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Solution

The fourth proportional to 640.31, 960.24 and 315.90 is: 473.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.31 : 960.24 = 315.90 : x
  2. Step 2: Convert to fraction form
    640.31/960.24 = 315.90/x
  3. Step 3: Cross multiply
    640.31x = 960.24 × 315.90
  4. Step 4: Simplify right side
    640.31x = 303,339.82
  5. Step 5: Solve for x
    x = 303,339.82/640.31
  6. Step 6: Final answer
    x = 473.74

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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.