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Finding the Fourth Proportional to 646.16, 969.22 and 280.90

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Solution

The fourth proportional to 646.16, 969.22 and 280.90 is: 421.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.16 : 969.22 = 280.90 : x
  2. Step 2: Convert to fraction form
    646.16/969.22 = 280.90/x
  3. Step 3: Cross multiply
    646.16x = 969.22 × 280.90
  4. Step 4: Simplify right side
    646.16x = 272,253.90
  5. Step 5: Solve for x
    x = 272,253.90/646.16
  6. Step 6: Final answer
    x = 421.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.