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Finding the Fourth Proportional to 661.77, 991.17 and 649.07

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Solution

The fourth proportional to 661.77, 991.17 and 649.07 is: 972.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.77 : 991.17 = 649.07 : x
  2. Step 2: Convert to fraction form
    661.77/991.17 = 649.07/x
  3. Step 3: Cross multiply
    661.77x = 991.17 × 649.07
  4. Step 4: Simplify right side
    661.77x = 643,338.71
  5. Step 5: Solve for x
    x = 643,338.71/661.77
  6. Step 6: Final answer
    x = 972.15

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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.