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Finding the Fourth Proportional to 642.08, 964.02 and 398.90

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Solution

The fourth proportional to 642.08, 964.02 and 398.90 is: 598.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.08 : 964.02 = 398.90 : x
  2. Step 2: Convert to fraction form
    642.08/964.02 = 398.90/x
  3. Step 3: Cross multiply
    642.08x = 964.02 × 398.90
  4. Step 4: Simplify right side
    642.08x = 384,547.58
  5. Step 5: Solve for x
    x = 384,547.58/642.08
  6. Step 6: Final answer
    x = 598.91

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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.