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Finding the Fourth Proportional to 420.30, 577.59 and 401.28

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Solution

The fourth proportional to 420.30, 577.59 and 401.28 is: 551.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.30 : 577.59 = 401.28 : x
  2. Step 2: Convert to fraction form
    420.30/577.59 = 401.28/x
  3. Step 3: Cross multiply
    420.30x = 577.59 × 401.28
  4. Step 4: Simplify right side
    420.30x = 231,775.32
  5. Step 5: Solve for x
    x = 231,775.32/420.30
  6. Step 6: Final answer
    x = 551.45

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.