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Finding the Fourth Proportional to 645.05, 889.89 and 435.08

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Solution

The fourth proportional to 645.05, 889.89 and 435.08 is: 600.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.05 : 889.89 = 435.08 : x
  2. Step 2: Convert to fraction form
    645.05/889.89 = 435.08/x
  3. Step 3: Cross multiply
    645.05x = 889.89 × 435.08
  4. Step 4: Simplify right side
    645.05x = 387,173.34
  5. Step 5: Solve for x
    x = 387,173.34/645.05
  6. Step 6: Final answer
    x = 600.22

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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.