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Finding the Fourth Proportional to 647.61, 887.68 and 638.50

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Solution

The fourth proportional to 647.61, 887.68 and 638.50 is: 875.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.61 : 887.68 = 638.50 : x
  2. Step 2: Convert to fraction form
    647.61/887.68 = 638.50/x
  3. Step 3: Cross multiply
    647.61x = 887.68 × 638.50
  4. Step 4: Simplify right side
    647.61x = 566,783.68
  5. Step 5: Solve for x
    x = 566,783.68/647.61
  6. Step 6: Final answer
    x = 875.19

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.