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Finding the Fourth Proportional to 661.10, 979.22 and 653.81

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Solution

The fourth proportional to 661.10, 979.22 and 653.81 is: 968.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.10 : 979.22 = 653.81 : x
  2. Step 2: Convert to fraction form
    661.10/979.22 = 653.81/x
  3. Step 3: Cross multiply
    661.10x = 979.22 × 653.81
  4. Step 4: Simplify right side
    661.10x = 640,220.57
  5. Step 5: Solve for x
    x = 640,220.57/661.10
  6. Step 6: Final answer
    x = 968.42

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.