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Finding the Fourth Proportional to 385, 531.30 and 210.35

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Solution

The fourth proportional to 385, 531.30 and 210.35 is: 290.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    385 : 531.30 = 210.35 : x
  2. Step 2: Convert to fraction form
    385/531.30 = 210.35/x
  3. Step 3: Cross multiply
    385x = 531.30 × 210.35
  4. Step 4: Simplify right side
    385x = 111,756.30
  5. Step 5: Solve for x
    x = 111,756.30/385
  6. Step 6: Final answer
    x = 290.28

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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.