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Finding the Fourth Proportional to 640.78, 962.99 and 316.37

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Solution

The fourth proportional to 640.78, 962.99 and 316.37 is: 475.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.78 : 962.99 = 316.37 : x
  2. Step 2: Convert to fraction form
    640.78/962.99 = 316.37/x
  3. Step 3: Cross multiply
    640.78x = 962.99 × 316.37
  4. Step 4: Simplify right side
    640.78x = 304,661.15
  5. Step 5: Solve for x
    x = 304,661.15/640.78
  6. Step 6: Final answer
    x = 475.45

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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.