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Finding the Fourth Proportional to 645.30, 889.92 and 383.13

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Solution

The fourth proportional to 645.30, 889.92 and 383.13 is: 528.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 889.92 = 383.13 : x
  2. Step 2: Convert to fraction form
    645.30/889.92 = 383.13/x
  3. Step 3: Cross multiply
    645.30x = 889.92 × 383.13
  4. Step 4: Simplify right side
    645.30x = 340,955.05
  5. Step 5: Solve for x
    x = 340,955.05/645.30
  6. Step 6: Final answer
    x = 528.37

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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.