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Finding the Fourth Proportional to 661.56, 912.34 and 412.90

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Solution

The fourth proportional to 661.56, 912.34 and 412.90 is: 569.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.56 : 912.34 = 412.90 : x
  2. Step 2: Convert to fraction form
    661.56/912.34 = 412.90/x
  3. Step 3: Cross multiply
    661.56x = 912.34 × 412.90
  4. Step 4: Simplify right side
    661.56x = 376,703.42
  5. Step 5: Solve for x
    x = 376,703.42/661.56
  6. Step 6: Final answer
    x = 569.42

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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.