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Finding the Fourth Proportional to 420.12, 633.09 and 400.20

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Solution

The fourth proportional to 420.12, 633.09 and 400.20 is: 603.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.12 : 633.09 = 400.20 : x
  2. Step 2: Convert to fraction form
    420.12/633.09 = 400.20/x
  3. Step 3: Cross multiply
    420.12x = 633.09 × 400.20
  4. Step 4: Simplify right side
    420.12x = 253,362.62
  5. Step 5: Solve for x
    x = 253,362.62/420.12
  6. Step 6: Final answer
    x = 603.07

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.