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Finding the Fourth Proportional to 642.91, 962.80 and 436.85

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Solution

The fourth proportional to 642.91, 962.80 and 436.85 is: 654.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.91 : 962.80 = 436.85 : x
  2. Step 2: Convert to fraction form
    642.91/962.80 = 436.85/x
  3. Step 3: Cross multiply
    642.91x = 962.80 × 436.85
  4. Step 4: Simplify right side
    642.91x = 420,598.18
  5. Step 5: Solve for x
    x = 420,598.18/642.91
  6. Step 6: Final answer
    x = 654.21

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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.