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Finding the Fourth Proportional to 645.31, 889.98 and 435.45

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Solution

The fourth proportional to 645.31, 889.98 and 435.45 is: 600.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.31 : 889.98 = 435.45 : x
  2. Step 2: Convert to fraction form
    645.31/889.98 = 435.45/x
  3. Step 3: Cross multiply
    645.31x = 889.98 × 435.45
  4. Step 4: Simplify right side
    645.31x = 387,540.16
  5. Step 5: Solve for x
    x = 387,540.16/645.31
  6. Step 6: Final answer
    x = 600.55

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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.