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Finding the Fourth Proportional to 661.14, 912.24 and 428.22

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Solution

The fourth proportional to 661.14, 912.24 and 428.22 is: 590.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.14 : 912.24 = 428.22 : x
  2. Step 2: Convert to fraction form
    661.14/912.24 = 428.22/x
  3. Step 3: Cross multiply
    661.14x = 912.24 × 428.22
  4. Step 4: Simplify right side
    661.14x = 390,639.41
  5. Step 5: Solve for x
    x = 390,639.41/661.14
  6. Step 6: Final answer
    x = 590.86

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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.