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Finding the Fourth Proportional to 610.40, 842.50 and 389.18

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Solution

The fourth proportional to 610.40, 842.50 and 389.18 is: 537.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    610.40 : 842.50 = 389.18 : x
  2. Step 2: Convert to fraction form
    610.40/842.50 = 389.18/x
  3. Step 3: Cross multiply
    610.40x = 842.50 × 389.18
  4. Step 4: Simplify right side
    610.40x = 327,884.15
  5. Step 5: Solve for x
    x = 327,884.15/610.40
  6. Step 6: Final answer
    x = 537.16

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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.