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Finding the Fourth Proportional to 728.84, 1,005.65 and 434.21

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Solution

The fourth proportional to 728.84, 1,005.65 and 434.21 is: 599.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.84 : 1,005.65 = 434.21 : x
  2. Step 2: Convert to fraction form
    728.84/1,005.65 = 434.21/x
  3. Step 3: Cross multiply
    728.84x = 1,005.65 × 434.21
  4. Step 4: Simplify right side
    728.84x = 436,657.72
  5. Step 5: Solve for x
    x = 436,657.72/728.84
  6. Step 6: Final answer
    x = 599.11

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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.