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Finding the Fourth Proportional to 645.18, 889.94 and 383

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Solution

The fourth proportional to 645.18, 889.94 and 383 is: 528.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.18 : 889.94 = 383 : x
  2. Step 2: Convert to fraction form
    645.18/889.94 = 383/x
  3. Step 3: Cross multiply
    645.18x = 889.94 × 383
  4. Step 4: Simplify right side
    645.18x = 340,847.02
  5. Step 5: Solve for x
    x = 340,847.02/645.18
  6. Step 6: Final answer
    x = 528.30

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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.