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Finding the Fourth Proportional to 642.09, 961.80 and 410.88

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Solution

The fourth proportional to 642.09, 961.80 and 410.88 is: 615.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.09 : 961.80 = 410.88 : x
  2. Step 2: Convert to fraction form
    642.09/961.80 = 410.88/x
  3. Step 3: Cross multiply
    642.09x = 961.80 × 410.88
  4. Step 4: Simplify right side
    642.09x = 395,184.38
  5. Step 5: Solve for x
    x = 395,184.38/642.09
  6. Step 6: Final answer
    x = 615.47

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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.