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Finding the Fourth Proportional to 648.40, 968.20 and 509.89

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Solution

The fourth proportional to 648.40, 968.20 and 509.89 is: 761.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.40 : 968.20 = 509.89 : x
  2. Step 2: Convert to fraction form
    648.40/968.20 = 509.89/x
  3. Step 3: Cross multiply
    648.40x = 968.20 × 509.89
  4. Step 4: Simplify right side
    648.40x = 493,675.50
  5. Step 5: Solve for x
    x = 493,675.50/648.40
  6. Step 6: Final answer
    x = 761.37

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.