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Finding the Fourth Proportional to 645.30, 889.86 and 552.35

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Solution

The fourth proportional to 645.30, 889.86 and 552.35 is: 761.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 889.86 = 552.35 : x
  2. Step 2: Convert to fraction form
    645.30/889.86 = 552.35/x
  3. Step 3: Cross multiply
    645.30x = 889.86 × 552.35
  4. Step 4: Simplify right side
    645.30x = 491,511.41
  5. Step 5: Solve for x
    x = 491,511.41/645.30
  6. Step 6: Final answer
    x = 761.68

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.