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Finding the Fourth Proportional to 661.35, 912.13 and 412.20

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Solution

The fourth proportional to 661.35, 912.13 and 412.20 is: 568.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.35 : 912.13 = 412.20 : x
  2. Step 2: Convert to fraction form
    661.35/912.13 = 412.20/x
  3. Step 3: Cross multiply
    661.35x = 912.13 × 412.20
  4. Step 4: Simplify right side
    661.35x = 375,979.99
  5. Step 5: Solve for x
    x = 375,979.99/661.35
  6. Step 6: Final answer
    x = 568.50

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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.