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Finding the Fourth Proportional to 642.68, 962.40 and 545

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Solution

The fourth proportional to 642.68, 962.40 and 545 is: 816.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.68 : 962.40 = 545 : x
  2. Step 2: Convert to fraction form
    642.68/962.40 = 545/x
  3. Step 3: Cross multiply
    642.68x = 962.40 × 545
  4. Step 4: Simplify right side
    642.68x = 524,508
  5. Step 5: Solve for x
    x = 524,508/642.68
  6. Step 6: Final answer
    x = 816.13

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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.