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Finding the Fourth Proportional to 807.53, 1,208.12 and 643.50

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Solution

The fourth proportional to 807.53, 1,208.12 and 643.50 is: 962.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.53 : 1,208.12 = 643.50 : x
  2. Step 2: Convert to fraction form
    807.53/1,208.12 = 643.50/x
  3. Step 3: Cross multiply
    807.53x = 1,208.12 × 643.50
  4. Step 4: Simplify right side
    807.53x = 777,422.00
  5. Step 5: Solve for x
    x = 777,422.00/807.53
  6. Step 6: Final answer
    x = 962.72

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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.