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Finding the Fourth Proportional to 405.30, 607.22 and 261.30

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Solution

The fourth proportional to 405.30, 607.22 and 261.30 is: 391.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.30 : 607.22 = 261.30 : x
  2. Step 2: Convert to fraction form
    405.30/607.22 = 261.30/x
  3. Step 3: Cross multiply
    405.30x = 607.22 × 261.30
  4. Step 4: Simplify right side
    405.30x = 158,666.59
  5. Step 5: Solve for x
    x = 158,666.59/405.30
  6. Step 6: Final answer
    x = 391.48

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.