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Finding the Fourth Proportional to 642.96, 965.98 and 412.30

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Solution

The fourth proportional to 642.96, 965.98 and 412.30 is: 619.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.96 : 965.98 = 412.30 : x
  2. Step 2: Convert to fraction form
    642.96/965.98 = 412.30/x
  3. Step 3: Cross multiply
    642.96x = 965.98 × 412.30
  4. Step 4: Simplify right side
    642.96x = 398,268.20
  5. Step 5: Solve for x
    x = 398,268.20/642.96
  6. Step 6: Final answer
    x = 619.43

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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.