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Finding the Fourth Proportional to 642.68, 887.46 and 407

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Solution

The fourth proportional to 642.68, 887.46 and 407 is: 562.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.68 : 887.46 = 407 : x
  2. Step 2: Convert to fraction form
    642.68/887.46 = 407/x
  3. Step 3: Cross multiply
    642.68x = 887.46 × 407
  4. Step 4: Simplify right side
    642.68x = 361,196.22
  5. Step 5: Solve for x
    x = 361,196.22/642.68
  6. Step 6: Final answer
    x = 562.02

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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.