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Finding the Fourth Proportional to 646.50, 969.42 and 213.50

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Solution

The fourth proportional to 646.50, 969.42 and 213.50 is: 320.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.50 : 969.42 = 213.50 : x
  2. Step 2: Convert to fraction form
    646.50/969.42 = 213.50/x
  3. Step 3: Cross multiply
    646.50x = 969.42 × 213.50
  4. Step 4: Simplify right side
    646.50x = 206,971.17
  5. Step 5: Solve for x
    x = 206,971.17/646.50
  6. Step 6: Final answer
    x = 320.14

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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.