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Finding the Fourth Proportional to 648.34, 971.81 and 319.51

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Solution

The fourth proportional to 648.34, 971.81 and 319.51 is: 478.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.34 : 971.81 = 319.51 : x
  2. Step 2: Convert to fraction form
    648.34/971.81 = 319.51/x
  3. Step 3: Cross multiply
    648.34x = 971.81 × 319.51
  4. Step 4: Simplify right side
    648.34x = 310,503.01
  5. Step 5: Solve for x
    x = 310,503.01/648.34
  6. Step 6: Final answer
    x = 478.92

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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.