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Finding the Fourth Proportional to 661.21, 912.08 and 409.23

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Solution

The fourth proportional to 661.21, 912.08 and 409.23 is: 564.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.21 : 912.08 = 409.23 : x
  2. Step 2: Convert to fraction form
    661.21/912.08 = 409.23/x
  3. Step 3: Cross multiply
    661.21x = 912.08 × 409.23
  4. Step 4: Simplify right side
    661.21x = 373,251.70
  5. Step 5: Solve for x
    x = 373,251.70/661.21
  6. Step 6: Final answer
    x = 564.50

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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.