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Finding the Fourth Proportional to 661.77, 911.86 and 637.47

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Solution

The fourth proportional to 661.77, 911.86 and 637.47 is: 878.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.77 : 911.86 = 637.47 : x
  2. Step 2: Convert to fraction form
    661.77/911.86 = 637.47/x
  3. Step 3: Cross multiply
    661.77x = 911.86 × 637.47
  4. Step 4: Simplify right side
    661.77x = 581,281.80
  5. Step 5: Solve for x
    x = 581,281.80/661.77
  6. Step 6: Final answer
    x = 878.37

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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.