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Finding the Fourth Proportional to 684.78, 1,026.84 and 410.78

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Solution

The fourth proportional to 684.78, 1,026.84 and 410.78 is: 615.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.78 : 1,026.84 = 410.78 : x
  2. Step 2: Convert to fraction form
    684.78/1,026.84 = 410.78/x
  3. Step 3: Cross multiply
    684.78x = 1,026.84 × 410.78
  4. Step 4: Simplify right side
    684.78x = 421,805.34
  5. Step 5: Solve for x
    x = 421,805.34/684.78
  6. Step 6: Final answer
    x = 615.97

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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.