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Finding the Fourth Proportional to 642.10, 885.81 and 434.74

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Solution

The fourth proportional to 642.10, 885.81 and 434.74 is: 599.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.10 : 885.81 = 434.74 : x
  2. Step 2: Convert to fraction form
    642.10/885.81 = 434.74/x
  3. Step 3: Cross multiply
    642.10x = 885.81 × 434.74
  4. Step 4: Simplify right side
    642.10x = 385,097.04
  5. Step 5: Solve for x
    x = 385,097.04/642.10
  6. Step 6: Final answer
    x = 599.75

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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.