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Finding the Fourth Proportional to 385.08, 531.09 and 290.13

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Solution

The fourth proportional to 385.08, 531.09 and 290.13 is: 400.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.08 : 531.09 = 290.13 : x
  2. Step 2: Convert to fraction form
    385.08/531.09 = 290.13/x
  3. Step 3: Cross multiply
    385.08x = 531.09 × 290.13
  4. Step 4: Simplify right side
    385.08x = 154,085.14
  5. Step 5: Solve for x
    x = 154,085.14/385.08
  6. Step 6: Final answer
    x = 400.14

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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.