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Finding the Fourth Proportional to 642.77, 887.24 and 407.11

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Solution

The fourth proportional to 642.77, 887.24 and 407.11 is: 561.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.77 : 887.24 = 407.11 : x
  2. Step 2: Convert to fraction form
    642.77/887.24 = 407.11/x
  3. Step 3: Cross multiply
    642.77x = 887.24 × 407.11
  4. Step 4: Simplify right side
    642.77x = 361,204.28
  5. Step 5: Solve for x
    x = 361,204.28/642.77
  6. Step 6: Final answer
    x = 561.95

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Find fourth proportional to 321.38, 443.62 and 203.56
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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.