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Finding the Fourth Proportional to 661.28, 987.28 and 569.60

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Solution

The fourth proportional to 661.28, 987.28 and 569.60 is: 850.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.28 : 987.28 = 569.60 : x
  2. Step 2: Convert to fraction form
    661.28/987.28 = 569.60/x
  3. Step 3: Cross multiply
    661.28x = 987.28 × 569.60
  4. Step 4: Simplify right side
    661.28x = 562,354.69
  5. Step 5: Solve for x
    x = 562,354.69/661.28
  6. Step 6: Final answer
    x = 850.40

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.