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Finding the Fourth Proportional to 434.16, 654.28 and 390.87

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Solution

The fourth proportional to 434.16, 654.28 and 390.87 is: 589.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    434.16 : 654.28 = 390.87 : x
  2. Step 2: Convert to fraction form
    434.16/654.28 = 390.87/x
  3. Step 3: Cross multiply
    434.16x = 654.28 × 390.87
  4. Step 4: Simplify right side
    434.16x = 255,735.15
  5. Step 5: Solve for x
    x = 255,735.15/434.16
  6. Step 6: Final answer
    x = 589.04

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.