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Finding the Fourth Proportional to 648.37, 970.58 and 428.15

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Solution

The fourth proportional to 648.37, 970.58 and 428.15 is: 640.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.37 : 970.58 = 428.15 : x
  2. Step 2: Convert to fraction form
    648.37/970.58 = 428.15/x
  3. Step 3: Cross multiply
    648.37x = 970.58 × 428.15
  4. Step 4: Simplify right side
    648.37x = 415,557.32
  5. Step 5: Solve for x
    x = 415,557.32/648.37
  6. Step 6: Final answer
    x = 640.92

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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.